title: How to replace string in textfield iphone?
body: <p>I am working on barcode app.So when user enter barcode in textfield so when it match (-)insert in that string like this
  let suppose textfield.text =12345786
  so when it match it converted into 1234-5786
  it is inserted but not deleting from my textfield.text value when my text is 123457869 or 1234578 dash(-)is not removing and textfield.text becomes 1234----.
  here is my code tell me where i am doing wrong?
      NSMutableString *a = [NSMutableString stringWithString:textfield.text];</p>
  
  <pre><code>if([textfield.text floatValue]&gt;=8 ){ 
  
  
      [a insertString: @"-" atIndex: 4];
      //textfield.text = [textfield.text stringByReplacingOccurrencesOfString:@"-" withString:@""];
  
      textfield.text = a;
      NSLog(@"in if");
  
  }
    else if([textfield.text length]&lt;8){
  
  
      //[a insertString: @"" atIndex: 4];
      textfield.text = [textfield.text stringByReplacingOccurrencesOfString:@"-" withString:@""];
  
      NSLog(@"in else");
      //NSRange range = {4,5};
      //[a deleteCharactersInRange:range];
      //textfield .text = a;
  }
  </code></pre>