本文整理汇总了VB.NET中System.Reflection.Emit.MethodBuilder.GetILGenerator方法的典型用法代码示例。如果您正苦于以下问题:VB.NET MethodBuilder.GetILGenerator方法的具体用法?VB.NET MethodBuilder.GetILGenerator怎么用?VB.NET MethodBuilder.GetILGenerator使用的例子?那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类System.Reflection.Emit.MethodBuilder
的用法示例。
在下文中一共展示了MethodBuilder.GetILGenerator方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的VB.NET代码示例。
示例1: TestILGenerator
' 导入命名空间
Imports System.Threading
Imports System.Reflection
Imports System.Reflection.Emit
_
Class TestILGenerator
Public Shared Function DynamicDotProductGen() As Type
Dim ivType As Type = Nothing
Dim ctorParams() As Type = {GetType(Integer), GetType(Integer), GetType(Integer)}
Dim myDomain As AppDomain = Thread.GetDomain()
Dim myAsmName As New AssemblyName()
myAsmName.Name = "IntVectorAsm"
Dim myAsmBuilder As AssemblyBuilder = myDomain.DefineDynamicAssembly( _
myAsmName, _
AssemblyBuilderAccess.RunAndSave)
Dim IntVectorModule As ModuleBuilder = myAsmBuilder.DefineDynamicModule( _
"IntVectorModule", _
"Vector.dll")
Dim ivTypeBld As TypeBuilder = IntVectorModule.DefineType("IntVector", TypeAttributes.Public)
Dim xField As FieldBuilder = ivTypeBld.DefineField("x", _
GetType(Integer), _
FieldAttributes.Private)
Dim yField As FieldBuilder = ivTypeBld.DefineField("y", _
GetType(Integer), _
FieldAttributes.Private)
Dim zField As FieldBuilder = ivTypeBld.DefineField("z", _
GetType(Integer), _
FieldAttributes.Private)
Dim objType As Type = Type.GetType("System.Object")
Dim objCtor As ConstructorInfo = objType.GetConstructor(New Type() {})
Dim ivCtor As ConstructorBuilder = ivTypeBld.DefineConstructor( _
MethodAttributes.Public, _
CallingConventions.Standard, _
ctorParams)
Dim ctorIL As ILGenerator = ivCtor.GetILGenerator()
ctorIL.Emit(OpCodes.Ldarg_0)
ctorIL.Emit(OpCodes.Call, objCtor)
ctorIL.Emit(OpCodes.Ldarg_0)
ctorIL.Emit(OpCodes.Ldarg_1)
ctorIL.Emit(OpCodes.Stfld, xField)
ctorIL.Emit(OpCodes.Ldarg_0)
ctorIL.Emit(OpCodes.Ldarg_2)
ctorIL.Emit(OpCodes.Stfld, yField)
ctorIL.Emit(OpCodes.Ldarg_0)
ctorIL.Emit(OpCodes.Ldarg_3)
ctorIL.Emit(OpCodes.Stfld, zField)
ctorIL.Emit(OpCodes.Ret)
' Now, you'll construct the method find the dot product of two vectors. First,
' let's define the parameters that will be accepted by the method. In this case,
' it's an IntVector itself!
Dim dpParams() As Type = {ivTypeBld}
' Here, you create a MethodBuilder containing the
' name, the attributes (public, static, private, and so on),
' the return type (int, in this case), and a array of Type
' indicating the type of each parameter. Since the sole parameter
' is a IntVector, the very class you're creating, you will
' pass in the TypeBuilder (which is derived from Type) instead of
' a Type object for IntVector, avoiding an exception.
' -- This method would be declared in VB.NET as:
' Public Function DotProduct(IntVector aVector) As Integer
Dim dotProductMthd As MethodBuilder = ivTypeBld.DefineMethod("DotProduct", _
MethodAttributes.Public, GetType(Integer), _
dpParams)
' A ILGenerator can now be spawned, attached to the MethodBuilder.
Dim mthdIL As ILGenerator = dotProductMthd.GetILGenerator()
' Here's the body of our function, in MSIL form. We're going to find the
' "dot product" of the current vector instance with the passed vector
' instance. For reference purposes, the equation is:
' (x1 * x2) + (y1 * y2) + (z1 * z2) = the dot product
' First, you'll load the reference to the current instance "this"
' stored in argument 0 (ldarg.0) onto the stack. Ldfld, the subsequent
' instruction, will pop the reference off the stack and look up the
' field "x", specified by the FieldInfo token "xField".
mthdIL.Emit(OpCodes.Ldarg_0)
mthdIL.Emit(OpCodes.Ldfld, xField)
' That completed, the value stored at field "x" is now atop the stack.
' Now, you'll do the same for the object reference we passed as a
' parameter, stored in argument 1 (ldarg.1). After Ldfld executed,
' you'll have the value stored in field "x" for the passed instance
' atop the stack.
mthdIL.Emit(OpCodes.Ldarg_1)
mthdIL.Emit(OpCodes.Ldfld, xField)
' There will now be two values atop the stack - the "x" value for the
' current vector instance, and the "x" value for the passed instance.
' You'll now multiply them, and push the result onto the evaluation stack.
mthdIL.Emit(OpCodes.Mul_Ovf_Un)
' Now, repeat this for the "y" fields of both vectors.
mthdIL.Emit(OpCodes.Ldarg_0)
mthdIL.Emit(OpCodes.Ldfld, yField)
mthdIL.Emit(OpCodes.Ldarg_1)
mthdIL.Emit(OpCodes.Ldfld, yField)
mthdIL.Emit(OpCodes.Mul_Ovf_Un)
' At this time, the results of both multiplications should be atop
' the stack. You'll now add them and push the result onto the stack.
mthdIL.Emit(OpCodes.Add_Ovf_Un)
' Multiply both "z" field and push the result onto the stack.
mthdIL.Emit(OpCodes.Ldarg_0)
mthdIL.Emit(OpCodes.Ldfld, zField)
mthdIL.Emit(OpCodes.Ldarg_1)
mthdIL.Emit(OpCodes.Ldfld, zField)
mthdIL.Emit(OpCodes.Mul_Ovf_Un)
' Finally, add the result of multiplying the "z" fields with the
' result of the earlier addition, and push the result - the dot product -
' onto the stack.
mthdIL.Emit(OpCodes.Add_Ovf_Un)
' The "ret" opcode will pop the last value from the stack and return it
' to the calling method. You're all done!
mthdIL.Emit(OpCodes.Ret)
ivType = ivTypeBld.CreateType()
Return ivType
End Function 'DynamicDotProductGen
Public Shared Sub Main()
Dim IVType As Type = Nothing
Dim aVector1 As Object = Nothing
Dim aVector2 As Object = Nothing
Dim aVtypes() As Type = {GetType(Integer), GetType(Integer), GetType(Integer)}
Dim aVargs1() As Object = {10, 10, 10}
Dim aVargs2() As Object = {20, 20, 20}
' Call the method to build our dynamic class.
IVType = DynamicDotProductGen()
Dim myDTctor As ConstructorInfo = IVType.GetConstructor(aVtypes)
aVector1 = myDTctor.Invoke(aVargs1)
aVector2 = myDTctor.Invoke(aVargs2)
Console.WriteLine("---")
Dim passMe(0) As Object
passMe(0) = CType(aVector2, Object)
Console.WriteLine("(10, 10, 10) . (20, 20, 20) = {0}", _
IVType.InvokeMember("DotProduct", BindingFlags.InvokeMethod, _
Nothing, aVector1, passMe))
End Sub
End Class
' +++ OUTPUT +++
' ---
' (10, 10, 10) . (20, 20, 20) = 600