String Comparison help

Discussion in 'Mac Programming' started by bguy, Jul 14, 2009.

  1. bguy macrumors newbie

    May 30, 2009
    I am writing a Cocoa Program. I have reached a problem when I am trying to compare a user generated string to a constant. Right now I am trying to compare them by using
    if([abc stringValue] == @"xyz")
    Where abc is an editable text field.
    This doesn't work when I type xyz into abc and activate it. I know it is connected correctly as other functions are working. I believe it has to do with the null terminator or something, but I don't know how to fix the problem.
    Can someone help me with this?
  2. kainjow Moderator emeritus


    Jun 15, 2000
    [[abc stringValue] isEqualToString:@"xyz"]
  3. larkost macrumors 6502a

    Oct 13, 2007
    The problem is that you are comparing the string pointers in your example to see if they are pointing at the same object. The hard-coded string will point at a pre-compiled string constant (implementation detail) while the other will point at a different string object.

    As kainjow said, the correct approach is to use NSString's isEqualToString method to do the comparison.
  4. bguy thread starter macrumors newbie

    May 30, 2009

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