/// <summary>
/// Will reset the default value for this property on the component. If
/// there was a default value passed in as a DefaultValueAttribute, that
/// value will be set as the value of the property on the component. If
/// there was no default value passed in, a ResetXXX method will be looked
/// for. If one is found, it will be invoked. If one is not found, this
/// is a nop.
/// </summary>
public override void ResetValue(object component)
{
object invokee = GetInvocationTarget(_componentClass, component);
if (DefaultValue != s_noValue)
{
SetValue(component, DefaultValue);
}
else if (AmbientValue != s_noValue)
{
SetValue(component, AmbientValue);
}
else if (ResetMethodValue != null)
{
ISite site = GetSite(component);
IComponentChangeService changeService = null;
object oldValue = null;
object newValue;
// Announce that we are about to change this component
if (site != null)
{
changeService = (IComponentChangeService)site.GetService(typeof(IComponentChangeService));
Debug.Assert(!ComponentModelSwitches.CommonDesignerServices.Enabled || changeService != null, "IComponentChangeService not found");
}
// Make sure that it is ok to send the onchange events
if (changeService != null)
{
// invokee might be a type from mscorlib or system, GetMethodValue might return a NonPublic method
oldValue = GetMethodValue.Invoke(invokee, null);
try
{
changeService.OnComponentChanging(component, this);
}
catch (CheckoutException coEx)
{
if (coEx == CheckoutException.Canceled)
{
return;
}
throw;
}
}
if (ResetMethodValue != null)
{
ResetMethodValue.Invoke(invokee, null);
// Now notify the change service that the change was successful.
if (changeService != null)
{
newValue = GetMethodValue.Invoke(invokee, null);
changeService.OnComponentChanged(component, this, oldValue, newValue);
}
}
}
}
internal object ExtenderGetValue(IExtenderProvider provider, object component)
{
if (provider != null)
{
provider = (IExtenderProvider)GetInvocationTarget(_componentClass, provider);
return(GetMethodValue.Invoke(provider, new object[] { component }));
}
return(null);
}
/// <summary>
/// Retrieves the current value of the property on component,
/// invoking the getXXX method. An exception in the getXXX
/// method will pass through.
/// </summary>
public override object GetValue(object component)
{
Debug.WriteLine($"[{Name}]: GetValue({component?.GetType().Name ?? "(null)"})");
if (IsExtender)
{
Debug.WriteLine($"[{Name}]: ---> returning: null");
return(null);
}
Debug.Assert(component != null, "GetValue must be given a component");
if (component != null)
{
component = GetInvocationTarget(_componentClass, component);
try
{
return(GetMethodValue.Invoke(component, null));
}
catch (Exception t)
{
string name = null;
IComponent comp = component as IComponent;
ISite site = comp?.Site;
if (site?.Name != null)
{
name = site.Name;
}
if (name == null)
{
name = component.GetType().FullName;
}
if (t is TargetInvocationException)
{
t = t.InnerException;
}
string message = t.Message ?? t.GetType().Name;
throw new TargetInvocationException(SR.Format(SR.ErrorPropertyAccessorException, Name, name, message), t);
}
}
Debug.WriteLine("[" + Name + "]: ---> returning: null");
return(null);
}
/// <summary>
/// This will set value to be the new value of this property on the
/// component by invoking the setXXX method on the component. If the
/// value specified is invalid, the component should throw an exception
/// which will be passed up. The component designer should design the
/// property so that getXXX following a setXXX should return the value
/// passed in if no exception was thrown in the setXXX call.
/// </summary>
public override void SetValue(object component, object value)
{
Debug.WriteLine($"[{Name}]: SetValue({component?.GetType().Name ?? "(null)"}, {value?.GetType().Name ?? "(null)"})");
if (component != null)
{
ISite site = GetSite(component);
object oldValue = null;
object invokee = GetInvocationTarget(_componentClass, component);
if (!IsReadOnly)
{
IComponentChangeService changeService = null;
// Announce that we are about to change this component
if (site != null)
{
changeService = (IComponentChangeService)site.GetService(typeof(IComponentChangeService));
}
// Make sure that it is ok to send the onchange events
if (changeService != null)
{
oldValue = GetMethodValue.Invoke(invokee, null);
try
{
changeService.OnComponentChanging(component, this);
}
catch (CheckoutException coEx)
{
if (coEx == CheckoutException.Canceled)
{
return;
}
throw;
}
}
try
{
try
{
SetMethodValue.Invoke(invokee, new object[] { value });
OnValueChanged(invokee, EventArgs.Empty);
}
catch (Exception t)
{
// Give ourselves a chance to unwind properly before rethrowing the exception.
//
value = oldValue;
// If there was a problem setting the controls property then we get:
// ArgumentException (from properties set method)
// ==> Becomes inner exception of TargetInvocationException
// ==> caught here
if (t is TargetInvocationException && t.InnerException != null)
{
// Propagate the original exception up
throw t.InnerException;
}
else
{
throw;
}
}
}
finally
{
// Now notify the change service that the change was successful.
changeService?.OnComponentChanged(component, this, oldValue, value);
}
}
}
}
/// <include file='doc\ReflectPropertyDescriptor.uex' path='docs/doc[@for="ReflectPropertyDescriptor.GetValue"]/*' />
/// <devdoc>
/// Retrieves the current value of the property on component,
/// invoking the getXXX method. An exception in the getXXX
/// method will pass through.
/// </devdoc>
public override object GetValue(object component)
{
#if DEBUG
if (PropDescUsageSwitch.TraceVerbose)
{
string compName = "(null)";
if (component != null)
{
compName = component.ToString();
}
Debug.WriteLine("[" + Name + "]: GetValue(" + compName + ")");
}
#endif
if (IsExtender)
{
Debug.WriteLineIf(PropDescUsageSwitch.TraceVerbose, "[" + Name + "]: ---> returning: null");
return(null);
}
Debug.Assert(component != null, "GetValue must be given a component");
if (component != null)
{
component = GetInvokee(componentClass, component);
try {
return(GetMethodValue.Invoke(component, null));
}
catch (Exception t) {
string name = null;
if (component is IComponent)
{
ISite site = ((IComponent)component).Site;
if (site != null && site.Name != null)
{
name = site.Name;
}
}
if (name == null)
{
name = component.GetType().FullName;
}
if (t is TargetInvocationException)
{
t = t.InnerException;
}
string message = t.Message;
if (message == null)
{
message = t.GetType().Name;
}
throw new TargetInvocationException(SR.GetString(SR.ErrorPropertyAccessorException, Name, name, message), t);
}
}
Debug.WriteLineIf(PropDescUsageSwitch.TraceVerbose, "[" + Name + "]: ---> returning: null");
return(null);
}
/// <include file='doc\ReflectPropertyDescriptor.uex' path='docs/doc[@for="ReflectPropertyDescriptor.SetValue"]/*' />
/// <devdoc>
/// This will set value to be the new value of this property on the
/// component by invoking the setXXX method on the component. If the
/// value specified is invalid, the component should throw an exception
/// which will be passed up. The component designer should design the
/// property so that getXXX following a setXXX should return the value
/// passed in if no exception was thrown in the setXXX call.
/// </devdoc>
public override void SetValue(object component, object value)
{
#if DEBUG
if (PropDescUsageSwitch.TraceVerbose)
{
string compName = "(null)";
string valName = "(null)";
if (component != null)
{
compName = component.ToString();
}
if (value != null)
{
valName = value.ToString();
}
Debug.WriteLine("[" + Name + "]: SetValue(" + compName + ", " + valName + ")");
}
#endif
if (component != null)
{
ISite site = GetSite(component);
IComponentChangeService changeService = null;
object oldValue = null;
object invokee = GetInvokee(componentClass, component);
Debug.Assert(!IsReadOnly, "SetValue attempted on read-only property [" + Name + "]");
if (!IsReadOnly)
{
// Announce that we are about to change this component
//
if (site != null)
{
changeService = (IComponentChangeService)site.GetService(typeof(IComponentChangeService));
Debug.Assert(!CompModSwitches.CommonDesignerServices.Enabled || changeService != null, "IComponentChangeService not found");
}
// Make sure that it is ok to send the onchange events
//
if (changeService != null)
{
oldValue = GetMethodValue.Invoke(invokee, null);
try {
changeService.OnComponentChanging(component, this);
}
catch (CheckoutException coEx) {
if (coEx == CheckoutException.Canceled)
{
return;
}
throw coEx;
}
}
try {
try {
SetMethodValue.Invoke(invokee, new object[] { value });
OnValueChanged(invokee, EventArgs.Empty);
}
catch (Exception t) {
// Give ourselves a chance to unwind properly before rethrowing the exception (bug# 20221).
//
value = oldValue;
// If there was a problem setting the controls property then we get:
// ArgumentException (from properties set method)
// ==> Becomes inner exception of TargetInvocationException
// ==> caught here
if (t is TargetInvocationException && t.InnerException != null)
{
// Propagate the original exception up
throw t.InnerException;
}
else
{
throw t;
}
}
}
finally {
// Now notify the change service that the change was successful.
//
if (changeService != null)
{
changeService.OnComponentChanged(component, this, oldValue, value);
}
}
}
}
}