C# 位运算 判断是否为2的N次幂

C:\Documents and Settings\Administrator\桌面\is2N\is2N\bin\Debug\is2N.exe C:\Documents and Settings\Administrator\桌面\is2N\is2N\bin\Debug\is2N.pdb C:\Documents and Settings\Administrator\桌面\is2N\is2N\obj\x86\Debug\ResolveAssemblyReference.cache C:\Documents and Settings\Administrator\桌面\is2N\is2N\obj\x86\Debug\is2N.exe C:\Documents and Settings\Administrator\桌面\is2N\is2N\obj\x86\Debug\is2N.pdb