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Objective C parse hex string to integer

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By User



I would like to know how to parse a hex string, representing a number, in objective c. I am willing to use both an objective, or a C based method, either is fine.





example:







#01FFFFAB







should parse into the integer: 33554347





Any help would be appreciated!


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Comments

  1. Tips For AllApril 3, 2012 at 7:22 AM

    Joshua Weinberg's answer is mostly correct, however the Ox prefix is optional when scanning hexadecimal integers. If you have a string in the format #01FFFFAB, you can still use an NSScanner, but you can simply skip the first character.

    unsigned result = 0;
    NSScanner *scanner = [NSScanner scannerWithString:@"#01FFFFAB"];

    [scanner setScanLocation:1]; // bypass '#' character
    [scanner scanHexInt:&result];

    ReplyDelete
  2. Tips For AllApril 3, 2012 at 7:22 AM

    you can use NSScanner for this

    int outVal;
    NSScanner* scanner = [NSScanner scannerWithString:@"0x01FFFFAB];
    [scanner scanHexInt:&outVal];


    outVal will contain the int you're looking for. The 0x is optional.

    ReplyDelete
  3. Tips For AllApril 3, 2012 at 7:22 AM

    strtol() is your friend.

    It converts a string to a long, and you can pass the base of the number in. Strip that # sign off first though, or pass to strtol a pointer to the first numerical character.

    ReplyDelete

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