String-Extras.swift

//
//  String-Extras.swift
//  Swift Tools
//
//  Created by Fahim Farook on 23/7/14.
//  Copyright (c) 2014 RookSoft Pte. Ltd. All rights reserved.
//

#if os(iOS)
import UIKit
#else
import AppKit
#endif

extension String {
	func positionOf(sub:String)->Int {
		var pos = -1
		if let range = self.rangeOfString(sub) {
			if !range.isEmpty {
				pos = self.startIndex.distanceTo(range.startIndex)
			}
		}
		return pos
	}
	
	func subString(start:Int, length:Int = -1)->String {
		var len = length
		if len == -1 {
			len = characters.count - start
		}
		let st = startIndex.advancedBy(start)
		let en = st.advancedBy(len)
		let range = st ..< en
		return substringWithRange(range)
	}
	
	func urlEncoded()->String {
		let res:NSString = CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, self as NSString, nil,
			"!*'();:@&=+$,/?%#[]", CFStringConvertNSStringEncodingToEncoding(NSUTF8StringEncoding))
		return res as String
	}
	
	func urlDecoded()->String {
		let res:NSString = CFURLCreateStringByReplacingPercentEscapesUsingEncoding(kCFAllocatorDefault, self as NSString, "", CFStringConvertNSStringEncodingToEncoding(NSUTF8StringEncoding))
		return res as String
	}
	
	func range()->Range<String.Index> {
		return Range<String.Index>(startIndex ..< endIndex)
	}
}