C＃：不能分配给foreach迭代变量 [英] C#: Cannot assign to foreach iteration variable

问题描述

  if（pos.X + pixelRadius< 0）{
 pos.X = bounds.Width  -  pixelRadius; 
} else if（pos.X + pixelRadius> bounds.Width）{
 pos.X = pixelRadius; 
 
 
 if（pos.Y + pixelRadius <0）{
 pos.Y = bounds.Heigh  -  pixelRadius; 
} else if（pos.Y + pixelRadius> bounds.Height）{
 pos.Y = pixelRadius; 
 
 $ / code> 

我的第一本能是做这样的事情：

  foreach（float coord in new float [] {pos.X，pos.Y}）{
 float upperBound =（coord == pos .X？bounds.Width：bounds.Height）; 
 if（coord + pixelRadius <0）{
 coord = upperBound  -  pixelRadius; 
} else if（coord + pixelRadius> upperBound）{
 coord = pixelRadius; 
 
 
 $ / code $ / pre 
 
当然然后我得到错误信息： / b> 
 
 
 不能分配给'coord'，因为它是'foreach迭代变量'
  / pre> 
 
 
有什么办法可以将这段代码封装在一个循环中？或者不值得这样做，而且在第一种形式下可读性更高。
 
 
 
对于那些好奇的人来说：是的，这是实现环绕式的。  
 
解决方案
 
老实说，我觉得第一个版本更具可读性。第二个版本在一个循环中批量填充，然后...测试以查看哪个循环元素是？闻起来像 ... case 反模式给我。
 
I'm trying to condense this by wrapping it in a loop:
       if (pos.X + pixelRadius < 0) {
            pos.X = bounds.Width - pixelRadius;
        } else if (pos.X + pixelRadius > bounds.Width) {
            pos.X = pixelRadius;
        }

        if (pos.Y + pixelRadius < 0) {
            pos.Y = bounds.Heigh - pixelRadius;
        } else if (pos.Y + pixelRadius > bounds.Height) {
            pos.Y = pixelRadius;
        }
My first instinct was to do something like this:
        foreach (float coord in new float[] { pos.X, pos.Y }) {
            float upperBound = (coord == pos.X ? bounds.Width : bounds.Height);
            if (coord + pixelRadius < 0) {
                coord = upperBound - pixelRadius;
            } else if (coord + pixelRadius > upperBound) {
                coord = pixelRadius;
            }
        }
But of course then I get the error message:
Cannot assign to 'coord' because it is a 'foreach iteration variable'
Is there any way I can wrap this code in a loop? Or maybe it's not worth the effort, and it's more readable to leave in the first form.

For those who are curious: yes, this is implementing wrap-around. 
解决方案
Honestly, I think the first version is more readable. The second version batches stuff up in a loop and then ... tests to see which loop element it is??? Smells like for...case antipattern to me.

                        
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