/// <summary>
/// Loads a HeatExtension from a type description string.
/// </summary>
/// <param name="extension">The extension type description string.</param>
/// <returns>The loaded HeatExtension.</returns>
public static HeatExtension Load(string extension)
{
Type extensionType;
if (2 == extension.Split(',').Length)
{
extensionType = System.Type.GetType(extension);
if (null == extensionType)
{
throw new WixException(WixErrors.InvalidExtension(extension));
}
}
else
{
try
{
Assembly extensionAssembly = Assembly.Load(extension);
AssemblyDefaultHeatExtensionAttribute extensionAttribute = (AssemblyDefaultHeatExtensionAttribute)Attribute.GetCustomAttribute(extensionAssembly, typeof(AssemblyDefaultHeatExtensionAttribute));
extensionType = extensionAttribute.ExtensionType;
}
catch
{
throw new WixException(WixErrors.InvalidExtension(extension));
}
}
if (extensionType.IsSubclassOf(typeof(HeatExtension)))
{
return(Activator.CreateInstance(extensionType) as HeatExtension);
}
else
{
throw new WixException(WixErrors.InvalidExtension(extension, extensionType.ToString(), typeof(HeatExtension).ToString()));
}
}
/// <summary>
/// Loads a HeatExtension from a type description string.
/// </summary>
/// <param name="extension">The extension type description string.</param>
/// <returns>The loaded HeatExtension.</returns>
/// <remarks>
/// <paramref name="extension"/> can be in several different forms:
/// <list type="number">
/// <item><term>AssemblyQualifiedName (TopNamespace.SubNameSpace.ContainingClass+NestedClass, MyAssembly, Version=1.3.0.0, Culture=neutral, PublicKeyToken=b17a5c561934e089)</term></item>
/// <item><term>AssemblyName (MyAssembly, Version=1.3.0.0, Culture=neutral, PublicKeyToken=b17a5c561934e089)</term></item>
/// <item><term>Absolute path to an assembly (C:\MyExtensions\ExtensionAssembly.dll)</term></item>
/// <item><term>Filename of an assembly in the application directory (ExtensionAssembly.dll)</term></item>
/// <item><term>Relative path to an assembly (..\..\MyExtensions\ExtensionAssembly.dll)</term></item>
/// </list>
/// To specify a particular class to use, prefix the fully qualified class name to the assembly and separate them with a comma.
/// For example: "TopNamespace.SubNameSpace.ContainingClass+NestedClass, C:\MyExtensions\ExtensionAssembly.dll"
/// </remarks>
public static HeatExtension Load(string extension)
{
Type extensionType = null;
int commaIndex = extension.IndexOf(',');
string className = String.Empty;
string assemblyName = extension;
if (0 <= commaIndex)
{
className = extension.Substring(0, commaIndex);
assemblyName = (extension.Length <= commaIndex + 1 ? String.Empty : extension.Substring(commaIndex + 1));
}
className = className.Trim();
assemblyName = assemblyName.Trim();
if (null == extensionType && 0 < assemblyName.Length)
{
Assembly extensionAssembly;
// case 3: Absolute path to an assembly
if (Path.IsPathRooted(assemblyName))
{
extensionAssembly = ExtensionLoadFrom(assemblyName);
}
else
{
try
{
// case 2: AssemblyName
extensionAssembly = Assembly.Load(assemblyName);
}
catch (IOException e)
{
if (e is FileLoadException || e is FileNotFoundException)
{
try
{
// case 4: Filename of an assembly in the application directory
extensionAssembly = Assembly.Load(Path.GetFileNameWithoutExtension(assemblyName));
}
catch (IOException innerE)
{
if (innerE is FileLoadException || innerE is FileNotFoundException)
{
// case 5: Relative path to an assembly
// we want to use Assembly.Load when we can because it has some benefits over Assembly.LoadFrom
// (see the documentation for Assembly.LoadFrom). However, it may fail when the path is a relative
// path, so we should try Assembly.LoadFrom one last time. We could have detected a directory
// separator character and used Assembly.LoadFrom directly, but dealing with path canonicalization
// issues is something we don't want to deal with if we don't have to.
extensionAssembly = ExtensionLoadFrom(assemblyName);
}
else
{
throw new WixException(WixErrors.InvalidExtension(assemblyName, innerE.Message));
}
}
}
else
{
throw new WixException(WixErrors.InvalidExtension(assemblyName, e.Message));
}
}
}
if (0 < className.Length)
{
try
{
// case 1: AssemblyQualifiedName
extensionType = extensionAssembly.GetType(className, true /* throwOnError */, true /* ignoreCase */);
}
catch (Exception e)
{
throw new WixException(WixErrors.InvalidExtensionType(assemblyName, className, e.GetType().ToString(), e.Message));
}
}
else
{
// if no class name was specified, then let's hope the assembly defined a default WixExtension
AssemblyDefaultHeatExtensionAttribute extensionAttribute = (AssemblyDefaultHeatExtensionAttribute)Attribute.GetCustomAttribute(extensionAssembly, typeof(AssemblyDefaultHeatExtensionAttribute));
if (null != extensionAttribute)
{
extensionType = extensionAttribute.ExtensionType;
}
else
{
throw new WixException(WixErrors.InvalidExtensionType(assemblyName, typeof(AssemblyDefaultHeatExtensionAttribute).ToString()));
}
}
}
if (extensionType.IsSubclassOf(typeof(HeatExtension)))
{
return(Activator.CreateInstance(extensionType) as HeatExtension);
}
else
{
throw new WixException(WixErrors.InvalidExtensionType(extension, extensionType.ToString(), typeof(HeatExtension).ToString()));
}
}