我想基于两个示例提出与维护局部变量的闭包相关的问题:
public static Func<int, int> F2()
{
var local = 1;
Func<int, int> inc = delegate (int x)
{
local = local + 1;
return x + local;
};
return inc;
}
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现在,调用它会呈现正确的 Closure 工作机制
var inc2 = F2();
Console.WriteLine(inc2(10));
Console.WriteLine(inc2(10));
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输出结果:
12
13
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现在,替代版本:
public static Func<int, int> F1 = i =>
{
var local = 1;
Func<int, int> FInn = x =>
{
local++;
return local + x;
};
return FInn(i);
};
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调用这个:
var inc1 = F1;
Console.WriteLine(inc1(10)); …Run Code Online (Sandbox Code Playgroud)