The wonderful use of do{}while()

Sometimes you often see in code do{}while(0),do{}while(false) This kind of form that looks a little strange , In fact, using this method in the project is very wonderful , It can reduce many problems in functional logic return Or multi-layer nesting if...else... In the form of , It can be easily implemented. There is only one in the function return, See the following code ：

#include <stdlib.h>
#include <stdio.h>

// Permission check function 
bool DoCheck(int n)
{
	bool bRet = false;
	do 
	{
		if (n & 0x1)
		{
			bRet = true;
		}
		if (n & 0x2)
		{
			bRet = false;
			break;
		}
		if (n & 0x4)
		{
			bRet = false;
			break;
		}
		if (n & 0x10)
		{
			// without do...while In the form of , You may need to directly return Or nested multiple if...else...
			bRet = true;
			break;
		}
		if (n & 0x20)
		{
			bRet = true;
		}
		if (n & 0x40)
		{
			bRet = true;
		}
	} while (false);
	return bRet;
}

int main()
{
	// Permission to check 
	if (DoCheck(0x11))
	{
		printf("yes!\n");
	}
	else
	{
		printf("no\n");
	}
	system("pause");
	return 0;
}