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是否有一个绑定示例,其中 iOS 将一个块传递给 C#,然后从 c# 调用?

对该场景的唯一引用是在块回调中。 http://docs.xamarin.com/guides/ios/advanced_topics/binding_objective-c/binding_types_reference_guide#BlockCallback

我们的问题是该块被调用但它似乎丢失了上下文,即:应该具有值的局部变量会丢失值。

以下是伪代码示例,因为代码过于复杂,无法在此处发布:

Objective-C

void somemethod () { 
  int x = 10;
  Myclass *myobj = [[Myclass alloc] init];
  [myCSharpbinding callsome:123 withBlock:^(int val) {
      myobj.prop1 = val; // fails because myobj is null by the time C# calls the block
      // x is also 0 when c# calls the block
  }];

C#

//ApiDefinition.cs

// method within myCSharpbinding class:
void callsome(int value, [BlockCallback] MyBlock block);


public delegate void MyBlock(int val);
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