Merge 5 NSStrings in Objective-C

Question

I have multiple NSStrings and i wish to merge them into one other, here is my code so far...

NSString *newURL = [_parameters objectForKey:@"url"];
NSString *emailBody = @"Hey!<br>I just snipped my long url with <a href=\"http://itunes.com/app/SnippetySnip\"&gt;Snippety Snip for iPhone</a> in just a few seconds, why not check it out?<p><b><a href=\""+newURL+@"\">"+newURL+@"</a></b></p>";

Answer 1

You can try

NSString *emailBody = [ NSString stringWithFormat: @"Hey!<br>I just snipped my long url with <a href=\"http://itunes.com/app/SnippetySnip\"&gt;Snippety Snip for iPhone</a> in just a few seconds, why not check it out?<p><b><a href=\"%@\">%@</a></b></p>", newURL ];

Answer 2

Formatting string has better readability and less error-prone:

NSString *newURL = [_parameters objectForKey:@"url"];
NSString *emailBody = [NSString stringWithFormat:@"Hey!<br>I just snipped my long url with <a href=\"http://itunes.com/app/SnippetySnip\"&gt;Snippety Snip for iPhone</a> in just a few seconds, why not check it out?<p><b><a href=\"%@\">%@</a></b></p>", newUrl, newUrl];

Answer 3

You can concatenate strings in Cocoa using:

[NSString stringByAppendingString:]

Or you could use the [NSString stringWithFormat] method which will allow you to specify a C-style format string with a variable argument list to populate the escape sequences.

Answer 4

If you know the number of your existing strings, you can just concat them:

NSString* longString = [firstString stringByAppendingString:secondString];

or:

NSString* longString = [NSString stringWithFormat:@"A string: %@, a float: %1.2f", @"string", 31415.9265];

If you have an arbitrary number of strings, you could put them in an NSArray and join them with:

NSArray* chunks  = ... get an array, say by splitting it;
NSString* string = [chunks componentsJoinedByString: @" :-) "];

(Taken from http://borkware.com/quickies/one?topic=NSString)

Another good resource for string handling in Cocoa is: "String Programming Guide"

Answer 5

Given that you've got multiple strings I recommend using an Array:

NSArray *array = [NSArray arrayWithObjects:@"URL", @"person", "body"];
NSString *combined = [array componentsJoinedByString:@""];

Answer 6

hi all, i have a stupid question...

NSString *newURL = [_parameters objectForKey:@"url"];

when i use this i get error... here what is _parameters and how to declare it??