在我的应用程序中，我需要动态创建一个包含多个属性的类型。我知道在这种情况下，必须使用 ILGenerator 为属性的 getter 和 setter 方法生成 CIL。
经过反复试验，我终于得到了以下代码，它为我生成了一个 setter 方法：
MethodBuilder setMethod = customTypeBuilder.DefineMethod(propertyName + "_set", MethodAttributes.Public | MethodAttributes.HideBySig, null, new Type[] {propertyType});
ILGenerator setIlGenerator = setMethod.GetILGenerator();
setIlGenerator.Emit(OpCodes.Ldarg_0);
setIlGenerator.Emit(OpCodes.Ldarg_1);
setIlGenerator.Emit(OpCodes.Stfld, backingField);
setIlGenerator.Emit(OpCodes.Ret);
该代码工作得很好，但有一点我不明白。 为什么需要调用'Ldarg_0'指令？
我知道它引用了方法的隐式第一个参数，即“this”引用，因此setter的实际值存储在第二个论点。我认为仅调用 Ldarg_1 指令就足够了，这会将第二个参数推入堆栈（最后，在设置器中，我不需要检查“this”引用，因此我不需要对其进行任何操作），但这会导致当我尝试设置该属性的值时抛出 TargetInitationException 。
谢谢你！
in my application I need to dynamically create a type that contains multiple properties. I am aware that in cases such as this, one has to generate an CIL for both getter and setter methods of a property by using an ILGenerator.
More by a trial and error than anything else, I've finally arrived to the following code that generates a setter method for me:
MethodBuilder setMethod = customTypeBuilder.DefineMethod(propertyName + "_set", MethodAttributes.Public | MethodAttributes.HideBySig, null, new Type[] {propertyType});
ILGenerator setIlGenerator = setMethod.GetILGenerator();
setIlGenerator.Emit(OpCodes.Ldarg_0);
setIlGenerator.Emit(OpCodes.Ldarg_1);
setIlGenerator.Emit(OpCodes.Stfld, backingField);
setIlGenerator.Emit(OpCodes.Ret);
The code works well enough, but there is one thing I don't understand about it. Why is it necessary to call the 'Ldarg_0' instruction?
I know that it refers to the implicit first argument of the method, the "this" reference, so the actual value for the setter is stored in the second argument. I thought that it should be sufficient to call the Ldarg_1 instruction only, which would push the second argument to the stack (in the end, in the setter, I have no need of examining the "this" reference so I don't need to do anything with it), but this results in the TargetInvocationException being thrown when I attempt to set the value of the property.
Thank you!
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如果您没有将“this”值压入堆栈，Stfld 如何知道要更改哪个对象的字段？您可能会尝试编写这样的设置器：
基本上，
Stfld是 记录了，堆栈上需要两个值：一个用于新值的“目标”，另一个用于值本身。诚然，ECMA 335 中的堆栈转换图更清晰：换句话说：“stfld 将从堆栈中弹出顶部的两个元素”。
If you didn't push the "this" value onto the stack, how would
Stfldknow which object's field to change? You could be trying to write a setter like this:Basically,
Stfldis documented to need two values on the stack: one for the "target" of the new value, and one for the value itself. Admittedly the stack transition diagram in ECMA 335 is clearer:In other words: "stfld will pop the top two elements off the stack".