I want to trim the occurence of special characters in a string

```
String  has :    
prevs: Case Number                                                                    
____________________

```

In this i want to remove -------- this dash from this string .I have tried like this :

```
NSCharacterSet *trim = [NSCharacterSet characterSetWithCharactersInString:@"-"];
    NSString *stringNew = [[previousString2 componentsSeparatedByCharactersInSet:trim] componentsJoinedByString:@""];

```

Thanks in Advance!