Question

i have seen this block of code in this Stackoverflow as a answer of some ones question,i tried to impliment that in my code but i am not getting what kind of function is this and how can i call that

NSString * ReplaceFirstNewLine(NSString * original)
{
    NSMutableString * newString = [NSMutableString stringWithString:original];

    NSRange foundRange = [original rangeOfString:@"\n"];
    if (foundRange.location != NSNotFound)
    {
        [newString replaceCharactersInRange:foundRange
                                 withString:@""];
    }
    NSLog(@"%@",newString);
    return [[newString retain] autorelease];
}

i have tried to call this like [self ReplaceFirstNewLine(@"\nstirng\nstring")];
but its giving syntax error,can any one help me out

Answer 1

First of all, it’s not a method, it’s a C function, similar to NSLog, so use it as such:

NSString *results = ReplaceFirstNewLine(@"\nstirng\nstring");
NSLog(@"%@", results);

C-style-functions have advantages and disadvantages, and I’ll try to list some of them here:

Advantages:

• Speed. A C function is almost ALWAYS faster than an equivalent objective-c method, because there is no dynamic dispatch needed to call the function

• Pointers. It is much easier to get a pointer to a C-style function than it is to an Objective-C method, which makes it much better suited for C API callbacks

Disadvantages:

• iVars. In a C function, you cannot access the private variables of an object (even with a reference to it), without using runtime wizardry, at which point, it really isn’t worth it.

• No concept of self. You cannot use the self (or _cmd, for that matter) variables inside a C function, as each C function is independent of other functions inside your product.