Question

MFC, C++: CString character access logical comparison causes compile time error

Asked by: sternocera

Hello,

I have encountered an annoying problem in MFC. The attached code snippet causes these compile time errors:

error C2446: '==' : no conversion from 'const char *' to 'int'

error C2040: '==' : 'int' differs in levels of indirection from 'const char [2]'

I can't for the life of me figure out why this should be.....I've found very similar code on MSDN that does the same thing (comparing a CString's GetAt function with a char literal.)

Your help would be appreciated, as always!

Regards,
Sternocera

void MyApp::disinject(CString& arg)
{
	// this utility function allows users to include literal " ' "s and so on
	// it guards against SQL injection
	
	int j = arg.GetLength();
	for(int i =  0;i != j; ++i) // this bit won't build
	{
		arg.GetAt(i);
		if(arg.GetAt(i) == "'")
		{
			arg.Insert(i,"'"); // make ' into ''
			++j;
		}
 
	}
}

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Asked On: 2008-01-09 at 04:07:23ID23069142
Tags: cstring
,; mfc
,; compare
Topics: Windows MFC Programming
,; Windows Programming
,; C++ Programming Language
Participating Experts: 1
Points: 500
Comments: 5

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