我的字符串反转功能有什么问题？ （C＃）

char[] a = { 'o', 'r', 'a', 'n', 'g', 'e' };

for (int i = 0; i < a.Length/2; i++)
{        
  a[i] = (char)(((uint)a[i])|((uint)a[a.Length-(i+1)]));
  a[a.Length-(i+1)] = (char)(((uint)a[i])^((uint)a[a.Length-(i+1)]));
  a[i] = (char)(((uint)a[i])^((uint)a[a.Length-(i+1)]));
}
char[] a = { 'o', 'r', 'a', 'n', 'g', 'e' };

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