If statement is not evaluating correctly

Question

I am working on a console project and I just can't get this part to work.

void execute(char* argv[]) {
    char* printex = "print";
    if (argv[1] == printex) {
        print(argv);
    }
    else {
        cout << "Unknown function." << endl;
    }
}

Every time I type in "print" for argv[1], it thinks I have typed in something else. I tried putting in

cout << argv[1];

and the output was print. Why is it not working then?

Try defining `printex` as: `std::string printex = "print";` instead. — Jerry Coffin, Jul 02 '14 at 06:34
[Read this](http://stackoverflow.com/questions/3933614/c-string-using-equality-operator-for-comparing-two-strings-for-equality) — WhozCraig, Jul 02 '14 at 06:36

score 1 · Accepted Answer · answered Jul 02 '14 at 06:35

argv[1] is a char*, so is printex. Comparing them will compare the address they contain, not the actual string. So they will never be same. You can use std::string (which is safer), or in the current form, use strcmp for comparison.

if( strcmp( argv[1], printex) == 0 )
 //mathced

score 1 · Answer 2 · answered Jul 02 '14 at 06:36

1

Try to replace if (argv[1] == printex) with if (strcmp(argv[1], printex)==0) to compare strings (not pointers on strings).

answered Jul 02 '14 at 06:36

Ilya

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If statement is not evaluating correctly

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