Question

i’m having this problem when i’m separating a string into an array using the componentsSeparatedByString function in xcode.

so i create an array from this string:

theDataObject.stringstick = @"1 0 0 0 0 0 0 0 1 0 1 1 1 0 0 0";

stickerarray = [[NSMutableArray alloc] initWithArray:[theDataObject.stringstick componentsSeparatedByString:@" "]];

so in my mind i expect:

stickerarray = {@"1",@"0",@"0",@"0",@"0",@"0",@"0",@"0",@"1",@"0",@"1",@"1",@"1",@"0",@"0",@"0"}

so when i chuck it through an if statement to check if an index is = 1

for ( int n = 0; n <= 15; n++) {
    if ([stickerarray objectAtIndex:n] == @"1") {
        NSLog(@"this works %i", n);
    } else {
                NSLog(@"this did not work on %@", [stickerarray objectAtIndex:n]);
    }
}

this is what i get:

 this did not work on 1
 this did not work on 0
 this did not work on 0
 this did not work on 0
 this did not work on 0
 this did not work on 0
 this did not work on 0
 this did not work on 0
 this did not work on 1
 this did not work on 0
 this did not work on 1
 this did not work on 1
 this did not work on 1
 this did not work on 0
 this did not work on 0
 this did not work on 0

I was amazed when i found this didn’t work so i tried applying some queries:

NSLog(@"ns array value of %@",[stickerarray objectAtIndex:2] );
ns array value of 0

NSLog(@"%@", stickerarray);
(
1,
0,
0,
0,
0,
0,
0,
0,
1,
0,
1,
1,
1,
0,
0,
0

)

NSLog(@"%@", theDataObject.stringstick);
1 0 0 0 0 0 0 0 1 0 1 1 1 0 0 0

I suspect that it’s the @”1″ when i’m comparing it inside the if statement. Be a great help if you can fix this for me. Thanks 🙂

Answer 1

Your use of componentsSeparatedByString is probably working, but your test is flawed. In objective-c you need to use NSString’s isEqualToString. “==” compares the pointers of the two strings and would only be equal if they were pointing to the same instance of the string. You should use something more like:

[item isEqualToString:@"1"]