Generate string of random characters cocoa?

Question

I know how to generate random numbers, but what I really need is a string of random characters. This is what I have so far:

NSString *letters = @"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ123456789?%$";

    char generated;
    generated = //how do i define this?

    NSLog(@"generated =%c", generated);
    [textField setStringValue:generated];

Note that `char generated;` declares a variable holding *one* character, not an array of characters. Also, `setStringValue:` takes a pointer to an NSString object, not a C string. — Peter Hosey, Jul 01 '11 at 03:56
Do you want to generate a string of any random characters, including unprintables, or only characters in the `letters` string? — Peter Hosey, Jul 01 '11 at 03:56
Oh I see because a char data type holds only a single character. Yes so I got it working with NSMutableString. Thanks for the tips. Also the book you recommended is great! — , Jul 01 '11 at 05:21

score 2 · Answer 1 · answered Jun 06 '13 at 14:32

-(NSString*)generateRandomString:(int)num {
    NSMutableString* string = [NSMutableString stringWithCapacity:num];
    for (int i = 0; i < num; i++) {
        [string appendFormat:@"%C", (unichar)('a' + arc4random_uniform(25))];
    }
    return string;
}

then Call it like this for a 5 letter string:

NSString* string = [self generateRandomString:5];

score 1 · Accepted Answer · edited May 23 '17 at 11:50

1

See this SO Q & A.

Generate a random alphanumeric string in Cocoa

edited May 23 '17 at 11:50

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answered Jul 01 '11 at 03:51

Andrew

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Generate string of random characters cocoa?

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