How do I get the substring between braces? - ios

Question

I have a string as this.
NSString *myString = #"{53} balloons";
How do I get the substring 53 ?

Answer 1

NSString *myString = #"{53} balloons";
NSRange start = [myString rangeOfString:#"{"];
NSRange end = [myString rangeOfString:#"}"];
if (start.location != NSNotFound && end.location != NSNotFound && end.location > start.location) {
NSString *betweenBraces = [myString substringWithRange:NSMakeRange(start.location+1, end.location-(start.location+1))];
}
edit: Added range check, thx to Keab42 - good point.

Answer 2

Here is what I did.
NSString *myString = #"{53} balloons";
NSCharacterSet *delimiters = [NSCharacterSet characterSetWithCharactersInString:#"{}"];
NSArray *splitString = [myString componentsSeparatedByCharactersInSet:delimiters];
NSString *substring = [splitString objectAtIndex:1];
the substring is 53.

Answer 3

For Swift 4.2:
if let r1 = string.range(of: "{")?.upperBound,
let r2 = string.range(of: "}")?.lowerBound {
print (String(string[r1..<r2]))
}

Answer 4

You can use a regular expression to get the number between the braces. It might seem a bit complicated but the plus side is that it will find multiple numbers and the position of the number doesn't matter.
Swift 4.2:
let searchText = "{53} balloons {12} clowns {123} sparklers"
let regex = try NSRegularExpression(pattern: "\\{(\\d+)\\}", options: [])
let matches = regex.matches(in: searchText, options: [], range: NSRange(searchText.startIndex..., in: searchText))
matches.compactMap { Range($0.range(at: 1), in: searchText) }
.forEach { print("Number: \(searchText[$0])") }
Objective-C:
NSString *searchText = #"{53} balloons {12} clowns {123} sparklers";
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:#"\\{(\\d+)\\}"
options:0
error:nil];
NSArray *matches = [regex matchesInString:searchText
options:0
range:NSMakeRange(0, searchText.length)];
for (NSTextCheckingResult *r in matches)
{
NSRange numberRange = [r rangeAtIndex:1];
NSLog(#"Number: %#", [searchText substringWithRange:numberRange]);
}
This will print out:
Number: 53
Number: 12
Number: 123

Answer 5

Try this code.
NSString *myString = #"{53} balloons";
NSString *value = [myString substringWithRange:NSMakeRange(1,2)];

Answer 6

For Swift 2.1 :-
var start = strData?.rangeOfString("{")
var end = strData?.rangeOfString("}")
if (start!.location != NSNotFound && end!.location != NSNotFound && end!.location > start!.location) {
var betweenBraces = strData?.substringWithRange(NSMakeRange(start!.location + 1, end!.location-(start!.location + 1)))
print(betweenBraces)
}

Answer 7

I guess, your a looking for the NSScanner class, at least if you are addressing a general case. Have a look in Apples documentation.

Answer 8

Search the location for "{" and "}".
Take substring between those index.

Answer 9

Checked with any number of data:
NSString *str = #"{53} balloons";
NSArray* strary = [str componentsSeparatedByString: #"}"];
NSString* str1 = [strary objectAtIndex: 0];
NSString *str2 = [str1 stringByReplacingOccurrencesOfString:#"{" withString:#""];
NSLog(#"number = %#",str2);
Another method is
NSString *tmpStr = #"{53} balloons";
NSRange r1 = [tmpStr rangeOfString:#"{"];
NSRange r2 = [tmpStr rangeOfString:#"}"];
NSRange rSub = NSMakeRange(r1.location + r1.length, r2.location - r1.location - r1.length);
NSString *subString = [tmpStr substringWithRange:rSub];

Answer 10

If you don't know how many digits there will be, but you know it will always be enclosed with curly braces try this:
NSString *myString = #"{53} balloons";
NSRange startRange = [myString rangeOfString:#"{"];
NSRange endRange = [myString rangeOfString:#"}"];
if (startRange.location != NSNotFound && endRange.location != NSNotFound && endRange.location > startRange.location) {
NSString *value = [myString substringWithRange:NSMakeRange(startRange.location,endRange.ocation - startRange.location)];
}
There's probably a more efficient way to do it though.