/// <summary>
/// Use this static method to cast a wrapped proxy to a new wrapper proxy of the supplied type.
/// In English, use this to cast you base "COM" interface to a specialized interface.
/// E.G. Outlook Item -> MailItem
/// </summary>
/// <typeparam name="T">the type you want to cast to</typeparam>
/// <param name="wrapperProxy">The wrapper interface, e.g. something you got back from calling GetItem</param>
/// <returns>A new wrapper proxy for the specified type</returns>
public static T Cast <T>(object wrapperProxy)
{
if (wrapperProxy == null)
{
return(default(T));
}
Type newType = typeof(T);
COMWrapper oldWrapper = RemotingServices.GetRealProxy(wrapperProxy) as COMWrapper;
if (oldWrapper == null)
{
throw new ArgumentException("wrapper proxy was no COMWrapper");
}
if (oldWrapper._InterceptType.IsAssignableFrom(newType))
{
COMWrapper newWrapper = new COMWrapper(oldWrapper._COMObject, newType, oldWrapper._TargetName);
return((T)newWrapper.GetTransparentProxy());
}
throw new InvalidCastException(string.Format("{0} is not assignable from {1}", oldWrapper._InterceptType, newType));
}
/// <summary>
/// Dump the Type-Information for the COM type to the log, this uses reflection
/// </summary>
/// <param name="wrapperProxy">wrapperProxy to inspect</param>
public static void DumpTypeInfo(object wrapperProxy)
{
Type comType = COMWrapper.GetUnderlyingType(wrapperProxy);
if (comType == null)
{
LOG.InfoFormat("Can't get Typeinformation");
return;
}
LOG.InfoFormat("Type information for COM object with name: {0}", comType.Name);
try {
foreach (MemberInfo memberInfo in comType.GetMembers())
{
LOG.InfoFormat("Member: {0};", memberInfo.ToString());
}
} catch (Exception memberException) {
LOG.Error(memberException);
}
try {
foreach (PropertyInfo propertyInfo in comType.GetProperties())
{
LOG.InfoFormat("Property: {0};", propertyInfo.ToString());
}
} catch (Exception propertyException) {
LOG.Error(propertyException);
}
try {
foreach (FieldInfo fieldInfo in comType.GetFields())
{
LOG.InfoFormat("Field: {0};", fieldInfo.ToString());
}
} catch (Exception fieldException) {
LOG.Error(fieldException);
}
LOG.InfoFormat("Type information end.");
}
/// <summary>
/// Gets a COM object and returns the transparent proxy which intercepts all calls to the object
/// </summary>
/// <param name="type">Interface which defines the method and properties to intercept</param>
/// <returns>Transparent proxy to the real proxy for the object</returns>
/// <remarks>The <paramref name="type"/> must be an interface decorated with the <see cref="ComProgIdAttribute"/>attribute.</remarks>
public static T GetInstance <T>()
{
Type type = typeof(T);
if (null == type)
{
throw new ArgumentNullException("type");
}
if (!type.IsInterface)
{
throw new ArgumentException("The specified type must be an interface.", "type");
}
ComProgIdAttribute progIDAttribute = ComProgIdAttribute.GetAttribute(type);
if (null == progIDAttribute || null == progIDAttribute.Value || 0 == progIDAttribute.Value.Length)
{
throw new ArgumentException("The specified type must define a ComProgId attribute.", "type");
}
string progId = progIDAttribute.Value;
// Convert from clsid to Prog ID, if needed
if (progId.StartsWith("clsid:"))
{
Guid guid = new Guid(progId.Substring(6));
int result = ProgIDFromCLSID(ref guid, out progId);
if (result != 0)
{
//LOG.WarnFormat("Error {0} getting progId {1}", result, progIDAttribute.Value);
}
else
{
//LOG.InfoFormat("Mapped {0} to progId {1}", progIDAttribute.Value, progId);
}
}
object comObject = null;
try {
comObject = Marshal.GetActiveObject(progId);
} catch (COMException comE) {
if (comE.ErrorCode == MK_E_UNAVAILABLE)
{
//LOG.DebugFormat("No current instance of {0} object available.", progId);
}
else if (comE.ErrorCode == CO_E_CLASSSTRING)
{
//LOG.WarnFormat("Unknown progId {0}", progId);
}
else
{
//LOG.Warn("Error getting active object for " + progId, comE);
}
} catch (Exception) {
//LOG.Warn("Error getting active object for " + progId, e);
}
if (comObject != null)
{
COMWrapper wrapper = new COMWrapper(comObject, type);
return((T)wrapper.GetTransparentProxy());
}
return(default(T));
}
/// <summary>
/// Intercept method calls
/// </summary>
/// <param name="myMessage">
/// Contains information about the method being called
/// </param>
/// <returns>
/// A <see cref="ReturnMessage"/>.
/// </returns>
public override IMessage Invoke(IMessage myMessage)
{
IMethodCallMessage callMessage = myMessage as IMethodCallMessage;
if (null == callMessage)
{
//LOG.DebugFormat("Message type not implemented: {0}", myMessage.GetType().ToString());
return(null);
}
MethodInfo method = callMessage.MethodBase as MethodInfo;
if (null == method)
{
//LOG.DebugFormat("Unrecognized Invoke call: {0}", callMessage.MethodBase.ToString());
return(null);
}
object returnValue = null;
object[] outArgs = null;
int outArgsCount = 0;
string methodName = method.Name;
Type returnType = method.ReturnType;
BindingFlags flags = BindingFlags.InvokeMethod;
int argCount = callMessage.ArgCount;
object invokeObject;
Type invokeType;
Type byValType;
object[] args;
object arg;
COMWrapper[] originalArgs;
COMWrapper wrapper;
ParameterModifier[] argModifiers = null;
ParameterInfo[] parameters = null;
ParameterInfo parameter;
if ("Dispose" == methodName && 0 == argCount && typeof(void) == returnType)
{
this.Dispose();
}
else if ("ToString" == methodName && 0 == argCount && typeof(string) == returnType)
{
returnValue = this.ToString();
}
else if ("GetType" == methodName && 0 == argCount && typeof(System.Type) == returnType)
{
returnValue = this._InterceptType;
}
else if ("GetHashCode" == methodName && 0 == argCount && typeof(int) == returnType)
{
returnValue = this.GetHashCode();
}
else if ("Equals" == methodName && 1 == argCount && typeof(bool) == returnType)
{
returnValue = this.Equals(callMessage.Args[0]);
}
else if (1 == argCount && typeof(void) == returnType && (methodName.StartsWith("add_") || methodName.StartsWith("remove_")))
{
bool removeHandler = methodName.StartsWith("remove_");
methodName = methodName.Substring(removeHandler ? 7 : 4);
Delegate handler = callMessage.InArgs[0] as Delegate;
if (null == handler)
{
return(new ReturnMessage(new ArgumentNullException("handler"), callMessage));
}
}
else
{
invokeObject = this._COMObject;
invokeType = this._COMType;
if (methodName.StartsWith("get_"))
{
// Property Get
methodName = methodName.Substring(4);
flags = BindingFlags.GetProperty;
args = callMessage.InArgs;
}
else if (methodName.StartsWith("set_"))
{
// Property Set
methodName = methodName.Substring(4);
flags = BindingFlags.SetProperty;
args = callMessage.InArgs;
}
else
{
args = callMessage.Args;
if (null != args && 0 != args.Length)
{
// Modifiers for ref / out parameters
argModifiers = new ParameterModifier[1];
argModifiers[0] = new ParameterModifier(args.Length);
parameters = method.GetParameters();
for (int i = 0; i < parameters.Length; i++)
{
parameter = parameters[i];
if (parameter.IsOut || parameter.ParameterType.IsByRef)
{
argModifiers[0][i] = true;
outArgsCount++;
}
}
if (0 == outArgsCount)
{
argModifiers = null;
}
}
}
// Un-wrap wrapped COM objects before passing to the method
if (null == args || 0 == args.Length)
{
originalArgs = null;
}
else
{
originalArgs = new COMWrapper[args.Length];
for (int i = 0; i < args.Length; i++)
{
if (null != args[i] && RemotingServices.IsTransparentProxy(args[i]))
{
wrapper = RemotingServices.GetRealProxy(args[i]) as COMWrapper;
if (null != wrapper)
{
originalArgs[i] = wrapper;
args[i] = wrapper._COMObject;
}
}
else if (0 != outArgsCount && argModifiers[0][i])
{
byValType = GetByValType(parameters[i].ParameterType);
if (byValType.IsInterface)
{
// If we're passing a COM object by reference, and
// the parameter is null, we need to pass a
// DispatchWrapper to avoid a type mismatch exception.
if (null == args[i])
{
args[i] = new DispatchWrapper(null);
}
}
else if (typeof(Decimal) == byValType)
{
// If we're passing a decimal value by reference,
// we need to pass a CurrencyWrapper to avoid a
// type mismatch exception.
// http://support.microsoft.com/?kbid=837378
args[i] = new CurrencyWrapper(args[i]);
}
}
}
}
try {
returnValue = invokeType.InvokeMember(methodName, flags, null, invokeObject, args, argModifiers, null, null);
} catch (Exception ex) {
return(new ReturnMessage(ex, callMessage));
}
// Handle enum and interface return types
if (null != returnValue)
{
if (returnType.IsInterface)
{
// Wrap the returned value in an intercepting COM wrapper
if (Marshal.IsComObject(returnValue))
{
returnValue = COMWrapper.Wrap(returnValue, returnType);
}
}
else if (returnType.IsEnum)
{
// Convert to proper Enum type
returnValue = Enum.Parse(returnType, returnValue.ToString());
}
}
// Handle out args
if (0 != outArgsCount)
{
outArgs = new object[args.Length];
for (int i = 0; i < parameters.Length; i++)
{
if (!argModifiers[0][i])
{
continue;
}
arg = args[i];
if (null == arg)
{
continue;
}
parameter = parameters[i];
wrapper = null;
byValType = GetByValType(parameter.ParameterType);
if (typeof(Decimal) == byValType)
{
if (arg is CurrencyWrapper)
{
arg = ((CurrencyWrapper)arg).WrappedObject;
}
}
else if (byValType.IsEnum)
{
arg = Enum.Parse(byValType, arg.ToString());
}
else if (byValType.IsInterface)
{
if (Marshal.IsComObject(arg))
{
wrapper = originalArgs[i];
if (null != wrapper && wrapper._COMObject != arg)
{
wrapper.Dispose();
wrapper = null;
}
if (null == wrapper)
{
wrapper = new COMWrapper(arg, byValType);
}
arg = wrapper.GetTransparentProxy();
}
}
outArgs[i] = arg;
}
}
}
return(new ReturnMessage(returnValue, outArgs, outArgsCount, callMessage.LogicalCallContext, callMessage));
}
/// <summary>
/// Intercept method calls
/// </summary>
/// <param name="myMessage">
/// Contains information about the method being called
/// </param>
/// <returns>
/// A <see cref="ReturnMessage"/>.
/// </returns>
public override IMessage Invoke(IMessage myMessage)
{
IMethodCallMessage callMessage = myMessage as IMethodCallMessage;
if (null == callMessage)
{
LOG.DebugFormat("Message type not implemented: {0}", myMessage.GetType().ToString());
return(null);
}
MethodInfo method = callMessage.MethodBase as MethodInfo;
if (null == method)
{
LOG.DebugFormat("Unrecognized Invoke call: {0}", callMessage.MethodBase.ToString());
return(null);
}
object returnValue = null;
object[] outArgs = null;
int outArgsCount = 0;
string methodName = method.Name;
Type returnType = method.ReturnType;
BindingFlags flags = BindingFlags.InvokeMethod;
int argCount = callMessage.ArgCount;
object invokeObject;
Type invokeType;
Type byValType;
object[] args;
object arg;
COMWrapper[] originalArgs;
COMWrapper wrapper;
ParameterModifier[] argModifiers = null;
ParameterInfo[] parameters = null;
ParameterInfo parameter;
if ("Dispose" == methodName && 0 == argCount && typeof(void) == returnType)
{
Dispose();
}
else if ("ToString" == methodName && 0 == argCount && typeof(string) == returnType)
{
returnValue = ToString();
}
else if ("GetType" == methodName && 0 == argCount && typeof(Type) == returnType)
{
returnValue = _InterceptType;
}
else if ("GetHashCode" == methodName && 0 == argCount && typeof(int) == returnType)
{
returnValue = GetHashCode();
}
else if ("Equals" == methodName && 1 == argCount && typeof(bool) == returnType)
{
returnValue = Equals(callMessage.Args[0]);
}
else if (1 == argCount && typeof(void) == returnType && (methodName.StartsWith("add_") || methodName.StartsWith("remove_")))
{
bool removeHandler = methodName.StartsWith("remove_");
methodName = methodName.Substring(removeHandler ? 7 : 4);
Delegate handler = callMessage.InArgs[0] as Delegate;
if (null == handler)
{
return(new ReturnMessage(new ArgumentNullException("handler"), callMessage));
}
}
else
{
invokeObject = _COMObject;
invokeType = _COMType;
if (methodName.StartsWith("get_"))
{
// Property Get
methodName = methodName.Substring(4);
flags = BindingFlags.GetProperty;
args = callMessage.InArgs;
}
else if (methodName.StartsWith("set_"))
{
// Property Set
methodName = methodName.Substring(4);
flags = BindingFlags.SetProperty;
args = callMessage.InArgs;
}
else
{
args = callMessage.Args;
if (null != args && 0 != args.Length)
{
// Modifiers for ref / out parameters
argModifiers = new ParameterModifier[1];
argModifiers[0] = new ParameterModifier(args.Length);
parameters = method.GetParameters();
for (int i = 0; i < parameters.Length; i++)
{
parameter = parameters[i];
if (parameter.IsOut || parameter.ParameterType.IsByRef)
{
argModifiers[0][i] = true;
outArgsCount++;
}
}
if (0 == outArgsCount)
{
argModifiers = null;
}
}
}
// Un-wrap wrapped COM objects before passing to the method
if (null == args || 0 == args.Length)
{
originalArgs = null;
}
else
{
originalArgs = new COMWrapper[args.Length];
for (int i = 0; i < args.Length; i++)
{
if (null != args[i] && RemotingServices.IsTransparentProxy(args[i]))
{
wrapper = RemotingServices.GetRealProxy(args[i]) as COMWrapper;
if (null != wrapper)
{
originalArgs[i] = wrapper;
args[i] = wrapper._COMObject;
}
}
else if (0 != outArgsCount && argModifiers[0][i])
{
byValType = GetByValType(parameters[i].ParameterType);
if (byValType.IsInterface)
{
// If we're passing a COM object by reference, and
// the parameter is null, we need to pass a
// DispatchWrapper to avoid a type mismatch exception.
if (null == args[i])
{
args[i] = new DispatchWrapper(null);
}
}
else if (typeof(Decimal) == byValType)
{
// If we're passing a decimal value by reference,
// we need to pass a CurrencyWrapper to avoid a
// type mismatch exception.
// http://support.microsoft.com/?kbid=837378
args[i] = new CurrencyWrapper(args[i]);
}
}
}
}
do
{
try
{
returnValue = invokeType.InvokeMember(methodName, flags, null, invokeObject, args, argModifiers, null, null);
break;
}
catch (Exception ex)
{
// Test for rejected
COMException comEx = ex as COMException;
if (comEx == null)
{
comEx = ex.InnerException as COMException;
}
if (comEx != null && (comEx.ErrorCode == RPC_E_CALL_REJECTED || comEx.ErrorCode == RPC_E_FAIL))
{
string destinationName = _TargetName;
// Try to find a "catchy" name for the rejecting application
if (destinationName != null && destinationName.Contains("."))
{
destinationName = destinationName.Substring(0, destinationName.IndexOf("."));
}
if (destinationName == null)
{
destinationName = _InterceptType.FullName;
}
DialogResult result = MessageBox.Show(Language.GetFormattedString("com_rejected", destinationName), Language.GetString("com_rejected_title"), MessageBoxButtons.OKCancel, MessageBoxIcon.Exclamation);
if (result == DialogResult.OK)
{
continue;
}
}
// Not rejected OR pressed cancel
return(new ReturnMessage(ex, callMessage));
}
} while (true);
// Handle enum and interface return types
if (null != returnValue)
{
if (returnType.IsInterface)
{
// Wrap the returned value in an intercepting COM wrapper
if (Marshal.IsComObject(returnValue))
{
returnValue = Wrap(returnValue, returnType, _TargetName);
}
}
else if (returnType.IsEnum)
{
// Convert to proper Enum type
returnValue = Enum.Parse(returnType, returnValue.ToString());
}
}
// Handle out args
if (0 != outArgsCount)
{
outArgs = new object[args.Length];
for (int i = 0; i < parameters.Length; i++)
{
if (!argModifiers[0][i])
{
continue;
}
arg = args[i];
if (null == arg)
{
continue;
}
parameter = parameters[i];
wrapper = null;
byValType = GetByValType(parameter.ParameterType);
if (typeof(Decimal) == byValType)
{
if (arg is CurrencyWrapper)
{
arg = ((CurrencyWrapper)arg).WrappedObject;
}
}
else if (byValType.IsEnum)
{
arg = Enum.Parse(byValType, arg.ToString());
}
else if (byValType.IsInterface)
{
if (Marshal.IsComObject(arg))
{
wrapper = originalArgs[i];
if (null != wrapper && wrapper._COMObject != arg)
{
wrapper.Dispose();
wrapper = null;
}
if (null == wrapper)
{
wrapper = new COMWrapper(arg, byValType, _TargetName);
}
arg = wrapper.GetTransparentProxy();
}
}
outArgs[i] = arg;
}
}
}
return(new ReturnMessage(returnValue, outArgs, outArgsCount, callMessage.LogicalCallContext, callMessage));
}
/// <summary>
/// Gets or creates a COM object and returns the transparent proxy which intercepts all calls to the object
/// The ComProgId can be a normal ComProgId or a GUID prefixed with "clsid:"
/// </summary>
/// <param name="type">Interface which defines the method and properties to intercept</param>
/// <returns>Transparent proxy to the real proxy for the object</returns>
/// <remarks>The <paramref name="type"/> must be an interface decorated with the <see cref="ComProgIdAttribute"/>attribute.</remarks>
public static T GetOrCreateInstance <T>()
{
Type type = typeof(T);
if (null == type)
{
throw new ArgumentNullException("type");
}
if (!type.IsInterface)
{
throw new ArgumentException("The specified type must be an interface.", "type");
}
ComProgIdAttribute progIDAttribute = ComProgIdAttribute.GetAttribute(type);
if (null == progIDAttribute || null == progIDAttribute.Value || 0 == progIDAttribute.Value.Length)
{
throw new ArgumentException("The specified type must define a ComProgId attribute.", "type");
}
object comObject = null;
Type comType = null;
string progId = progIDAttribute.Value;
Guid guid = Guid.Empty;
// Convert from clsid to Prog ID, if needed
if (progId.StartsWith("clsid:"))
{
guid = new Guid(progId.Substring(6));
int result = ProgIDFromCLSID(ref guid, out progId);
if (result != 0)
{
// Restore progId, as it's overwritten
progId = progIDAttribute.Value;
try
{
GetActiveObject(ref guid, IntPtr.Zero, out comObject);
}
catch (Exception)
{
LOG.WarnFormat("Error {0} getting instance for class id {1}", result, progIDAttribute.Value);
}
if (comObject == null)
{
LOG.WarnFormat("Error {0} getting progId {1}", result, progIDAttribute.Value);
}
}
else
{
LOG.InfoFormat("Mapped {0} to progId {1}", progIDAttribute.Value, progId);
}
}
if (comObject == null)
{
if (!progId.StartsWith("clsid:"))
{
try
{
comObject = Marshal.GetActiveObject(progId);
}
catch (COMException comE)
{
if (comE.ErrorCode == MK_E_UNAVAILABLE)
{
LOG.DebugFormat("No current instance of {0} object available.", progId);
}
else if (comE.ErrorCode == CO_E_CLASSSTRING)
{
LOG.WarnFormat("Unknown progId {0} (application not installed)", progId);
return(default(T));
}
else
{
LOG.Warn("Error getting active object for " + progId, comE);
}
}
catch (Exception e)
{
LOG.Warn("Error getting active object for " + progId, e);
}
}
}
// Did we get the current instance? If not, try to create a new
if (comObject == null)
{
try
{
comType = Type.GetTypeFromProgID(progId, true);
}
catch (Exception ex)
{
if (Guid.Empty != guid)
{
comType = Type.GetTypeFromCLSID(guid);
}
else
{
LOG.Warn("Error type for " + progId, ex);
}
}
if (comType != null)
{
try
{
comObject = Activator.CreateInstance(comType);
if (comObject != null)
{
LOG.DebugFormat("Created new instance of {0} object.", progId);
}
}
catch (Exception e)
{
LOG.Warn("Error creating object for " + progId, e);
}
}
}
if (comObject != null)
{
if (comObject is IDispatch)
{
COMWrapper wrapper = new COMWrapper(comObject, type, progIDAttribute.Value);
return((T)wrapper.GetTransparentProxy());
}
else
{
return((T)comObject);
}
}
return(default(T));
}
/// <summary>
/// Gets a COM object and returns the transparent proxy which intercepts all calls to the object
/// </summary>
/// <typeparam name="T">Interface which defines the method and properties to intercept</typeparam>
/// <returns>Transparent proxy to the real proxy for the object</returns>
/// <remarks>T must be an interface decorated with the <see cref="ComProgIdAttribute"/>attribute.</remarks>
public static T GetInstance <T>()
{
Type type = typeof(T);
if (null == type)
{
throw new ArgumentNullException(nameof(T));
}
if (!type.IsInterface)
{
throw new ArgumentException("The specified type must be an interface.", nameof(T));
}
var progIdAttribute = ComProgIdAttribute.GetAttribute(type);
if (string.IsNullOrEmpty(progIdAttribute?.Value))
{
throw new ArgumentException("The specified type must define a ComProgId attribute.", nameof(T));
}
string progId = progIdAttribute.Value;
object comObject = null;
// Convert from clsid to Prog ID, if needed
if (progId.StartsWith("clsid:"))
{
Guid guid = new Guid(progId.Substring(6));
int result = ProgIDFromCLSID(ref guid, out progId);
if (result != 0)
{
// Restore progId, as it's overwritten
progId = progIdAttribute.Value;
try {
GetActiveObject(ref guid, IntPtr.Zero, out comObject);
} catch (Exception) {
Log.WarnFormat("Error {0} getting instance for class id {1}", result, progIdAttribute.Value);
}
if (comObject == null)
{
Log.WarnFormat("Error {0} getting progId {1}", result, progIdAttribute.Value);
}
}
else
{
Log.InfoFormat("Mapped {0} to progId {1}", progIdAttribute.Value, progId);
}
}
if (comObject == null)
{
try {
comObject = Marshal.GetActiveObject(progId);
} catch (COMException comE) {
if (comE.ErrorCode == MK_E_UNAVAILABLE)
{
Log.DebugFormat("No current instance of {0} object available.", progId);
}
else if (comE.ErrorCode == CO_E_CLASSSTRING)
{
Log.WarnFormat("Unknown progId {0}", progId);
}
else
{
Log.Warn("Error getting active object for " + progIdAttribute.Value, comE);
}
} catch (Exception e) {
Log.Warn("Error getting active object for " + progIdAttribute.Value, e);
}
}
if (comObject != null)
{
if (comObject is IDispatch)
{
COMWrapper wrapper = new COMWrapper(comObject, type, progIdAttribute.Value);
return((T)wrapper.GetTransparentProxy());
}
else
{
return((T)comObject);
}
}
return(default(T));
}
/// <summary>
/// Gets or creates a COM object and returns the transparent proxy which intercepts all calls to the object
/// The ComProgId can be a normal ComProgId or a GUID prefixed with "clsid:"
/// </summary>
/// <typeparam name="T">Interface which defines the method and properties to intercept</typeparam>
/// <returns>Transparent proxy to the real proxy for the object</returns>
/// <remarks>The type must be an interface decorated with the <see cref="ComProgIdAttribute"/>attribute.</remarks>
public static T GetOrCreateInstance <T>()
{
Type type = typeof(T);
if (null == type)
{
throw new ArgumentNullException(nameof(T));
}
if (!type.IsInterface)
{
throw new ArgumentException("The specified type must be an interface.", nameof(T));
}
ComProgIdAttribute progIdAttribute = ComProgIdAttribute.GetAttribute(type);
if (string.IsNullOrEmpty(progIdAttribute?.Value))
{
throw new ArgumentException("The specified type must define a ComProgId attribute.", nameof(T));
}
object comObject = null;
Type comType = null;
string progId = progIdAttribute.Value;
try {
comObject = Marshal.GetActiveObject(progId);
} catch (COMException comE) {
if (comE.ErrorCode == MK_E_UNAVAILABLE)
{
Debug.WriteLine($"No current instance of {progId} object available.");
}
else if (comE.ErrorCode == CO_E_CLASSSTRING)
{
Debug.WriteLine($"Unknown progId {progId}");
}
} catch (Exception ex) {
Debug.WriteLine($"Error getting active object for {progId} {ex.Message}");
}
// Did we get the current instance? If not, try to create a new
if (comObject == null)
{
try {
comType = Type.GetTypeFromProgID(progId, true);
} catch (Exception) {
Debug.WriteLine($"Error getting type for {progId}");
}
if (comType != null)
{
try {
comObject = Activator.CreateInstance(comType);
if (comObject != null)
{
Debug.WriteLine($"Created new instance of {progId} object.");
}
} catch (Exception ex) {
Debug.WriteLine($"Error creating object for {progId} {ex.Message}");
}
}
}
if (comObject != null)
{
COMWrapper wrapper = new COMWrapper(comObject, type);
return((T)wrapper.GetTransparentProxy());
}
return(default(T));
}
/// <summary>
/// Intercept method calls
/// </summary>
/// <param name="myMessage">
/// Contains information about the method being called
/// </param>
/// <returns>
/// A <see cref="ReturnMessage"/>.
/// </returns>
public override IMessage Invoke(IMessage myMessage)
{
IMethodCallMessage callMessage = myMessage as IMethodCallMessage;
if (null == callMessage) {
LOG.DebugFormat("Message type not implemented: {0}", myMessage.GetType().ToString());
return null;
}
MethodInfo method = callMessage.MethodBase as MethodInfo;
if (null == method) {
LOG.DebugFormat("Unrecognized Invoke call: {0}", callMessage.MethodBase.ToString());
return null;
}
object returnValue = null;
object[] outArgs = null;
int outArgsCount = 0;
string methodName = method.Name;
Type returnType = method.ReturnType;
BindingFlags flags = BindingFlags.InvokeMethod;
int argCount = callMessage.ArgCount;
object invokeObject;
Type invokeType;
Type byValType;
object[] args;
object arg;
COMWrapper[] originalArgs;
COMWrapper wrapper;
ParameterModifier[] argModifiers = null;
ParameterInfo[] parameters = null;
ParameterInfo parameter;
if ("Dispose" == methodName && 0 == argCount && typeof(void) == returnType) {
this.Dispose();
} else if ("ToString" == methodName && 0 == argCount && typeof(string) == returnType) {
returnValue = this.ToString();
} else if ("GetType" == methodName && 0 == argCount && typeof(System.Type) == returnType) {
returnValue = this._InterceptType;
} else if ("GetHashCode" == methodName && 0 == argCount && typeof(int) == returnType) {
returnValue = this.GetHashCode();
} else if ("Equals" == methodName && 1 == argCount && typeof(bool) == returnType) {
returnValue = this.Equals(callMessage.Args[0]);
} else if (1 == argCount && typeof(void) == returnType && (methodName.StartsWith("add_") || methodName.StartsWith("remove_"))) {
bool removeHandler = methodName.StartsWith("remove_");
methodName = methodName.Substring(removeHandler ? 7 : 4);
Delegate handler = callMessage.InArgs[0] as Delegate;
if (null == handler) {
return new ReturnMessage(new ArgumentNullException("handler"), callMessage);
}
} else {
invokeObject = this._COMObject;
invokeType = this._COMType;
if (methodName.StartsWith("get_")) {
// Property Get
methodName = methodName.Substring(4);
flags = BindingFlags.GetProperty;
args = callMessage.InArgs;
} else if (methodName.StartsWith("set_")) {
// Property Set
methodName = methodName.Substring(4);
flags = BindingFlags.SetProperty;
args = callMessage.InArgs;
} else {
args = callMessage.Args;
if (null != args && 0 != args.Length) {
// Modifiers for ref / out parameters
argModifiers = new ParameterModifier[1];
argModifiers[0] = new ParameterModifier(args.Length);
parameters = method.GetParameters();
for(int i=0; i<parameters.Length; i++) {
parameter = parameters[i];
if (parameter.IsOut || parameter.ParameterType.IsByRef) {
argModifiers[0][i] = true;
outArgsCount++;
}
}
if (0 == outArgsCount) {
argModifiers = null;
}
}
}
// Un-wrap wrapped COM objects before passing to the method
if (null == args || 0 == args.Length) {
originalArgs = null;
} else {
originalArgs = new COMWrapper[args.Length];
for(int i=0; i<args.Length; i++) {
if (null != args[i] && RemotingServices.IsTransparentProxy(args[i])) {
wrapper = RemotingServices.GetRealProxy(args[i]) as COMWrapper;
if (null != wrapper) {
originalArgs[i] = wrapper;
args[i] = wrapper._COMObject;
}
} else if (0 != outArgsCount && argModifiers[0][i]) {
byValType = GetByValType(parameters[i].ParameterType);
if (byValType.IsInterface) {
// If we're passing a COM object by reference, and
// the parameter is null, we need to pass a
// DispatchWrapper to avoid a type mismatch exception.
if (null == args[i]) {
args[i] = new DispatchWrapper(null);
}
} else if (typeof(Decimal) == byValType) {
// If we're passing a decimal value by reference,
// we need to pass a CurrencyWrapper to avoid a
// type mismatch exception.
// http://support.microsoft.com/?kbid=837378
args[i] = new CurrencyWrapper(args[i]);
}
}
}
}
try {
returnValue = invokeType.InvokeMember(methodName, flags, null, invokeObject, args, argModifiers, null, null);
} catch(Exception ex) {
return new ReturnMessage(ex, callMessage);
}
// Handle enum and interface return types
if (null != returnValue) {
if (returnType.IsInterface) {
// Wrap the returned value in an intercepting COM wrapper
if (Marshal.IsComObject(returnValue)) {
returnValue = COMWrapper.Wrap(returnValue, returnType);
}
} else if (returnType.IsEnum) {
// Convert to proper Enum type
returnValue = Enum.Parse(returnType, returnValue.ToString());
}
}
// Handle out args
if (0 != outArgsCount) {
outArgs = new object[args.Length];
for(int i=0; i<parameters.Length; i++) {
if (!argModifiers[0][i]) {
continue;
}
arg = args[i];
if (null == arg) {
continue;
}
parameter = parameters[i];
wrapper = null;
byValType = GetByValType(parameter.ParameterType);
if (typeof(Decimal) == byValType) {
if (arg is CurrencyWrapper) {
arg = ((CurrencyWrapper)arg).WrappedObject;
}
} else if (byValType.IsEnum) {
arg = Enum.Parse(byValType, arg.ToString());
} else if (byValType.IsInterface) {
if (Marshal.IsComObject(arg)) {
wrapper = originalArgs[i];
if (null != wrapper && wrapper._COMObject != arg) {
wrapper.Dispose();
wrapper = null;
}
if (null == wrapper) {
wrapper = new COMWrapper(arg, byValType);
}
arg = wrapper.GetTransparentProxy();
}
}
outArgs[i] = arg;
}
}
}
return new ReturnMessage(returnValue, outArgs, outArgsCount, callMessage.LogicalCallContext, callMessage);
}
/// <summary>
/// Wrap an object and return the transparent proxy which intercepts all calls
/// to the object
/// </summary>
/// <param name="comObject">An object to intercept</param>
/// <param name="type">Interface which defines the method and properties to intercept</param>
/// <returns>Transparent proxy to the real proxy for the object</returns>
public static object Wrap(object comObject, Type type)
{
if (null == comObject) {
throw new ArgumentNullException("comObject");
}
if (null == type) {
throw new ArgumentNullException("type");
}
COMWrapper wrapper = new COMWrapper(comObject, type);
return wrapper.GetTransparentProxy();
}
/// <summary>
/// Gets a COM object and returns the transparent proxy
/// which intercepts all calls to the object
/// </summary>
/// <param name="type">Interface which defines the method and properties to intercept</param>
/// <returns>Transparent proxy to the real proxy for the object</returns>
/// <remarks>The <paramref name="type"/> must be an interface decorated with the <see cref="ComProgIdAttribute"/>attribute.</remarks>
public static object GetOrCreateInstance(Type type)
{
if (null == type) {
throw new ArgumentNullException("type");
}
if (!type.IsInterface) {
throw new ArgumentException("The specified type must be an interface.", "type");
}
ComProgIdAttribute progID = ComProgIdAttribute.GetAttribute(type);
if (null == progID || null == progID.Value || 0 == progID.Value.Length) {
throw new ArgumentException("The specified type must define a ComProgId attribute.", "type");
}
object comObject = null;
Type comType = Type.GetTypeFromProgID(progID.Value, true);
try {
comObject = Marshal.GetActiveObject(progID.Value);
} catch (COMException comE) {
if (comE.ErrorCode == MK_E_UNAVAILABLE) {
LOG.DebugFormat("No current instance of {0} object available.", progID.Value);
} else {
LOG.Warn("Error getting active object for " + progID.Value, comE);
}
} catch (Exception e) {
LOG.Warn("Error getting active object for " + progID.Value, e);
}
// Did we get the current instance? If not, try to create a new
if (comObject == null) {
try {
comObject = Activator.CreateInstance(comType);
if (comObject != null) {
LOG.DebugFormat("Created new instance of {0} object.", progID.Value);
}
} catch (Exception e) {
LOG.Warn("Error creating object for " + progID.Value, e);
}
}
if (comObject != null) {
COMWrapper wrapper = new COMWrapper(comObject, type);
return wrapper.GetTransparentProxy();
}
throw new TypeLoadException(string.Format("Unable to get or create an instance of the specified COM server \"{0}\".", progID.Value));
}
