{"id":25435,"date":"2015-08-11T22:12:31","date_gmt":"2015-08-11T16:42:31","guid":{"rendered":"https:\/\/2thenew.xyz\/blog\/?p=25435"},"modified":"2015-08-26T12:48:23","modified_gmt":"2015-08-26T07:18:23","slug":"common-utility-extensions-in-swift-utils-swift","status":"publish","type":"post","link":"https:\/\/2thenew.xyz\/blog\/common-utility-extensions-in-swift-utils-swift\/","title":{"rendered":"Common Utility Extensions in Swift (Utils.swift)"},"content":{"rendered":"

What is Extension:<\/h1>\n

Extensions are basically similar to an Objective-C category. Extensions are sort of methods adding in a Classe or Structure in a different flavour.<\/p>\n

Syntax of Extension:<\/h1>\n

The syntax to create an extension is very similar to creating a type. You can write the following code in your Utils.swift class to add a UIColor<\/b>\u00a0extension.<\/p>\n

\n\n\n\n
\n
extension UIColor<\/span>\r\n{\r\n    \/\/Fill in the blank\r\n}<\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
Common Extensions List:<\/h1>\n
NSData\u00a0Extensions:<\/h3>\n
\n\n\n\n
\n
\/\/MARK: NSData Extensions\r\nextension NSData<\/span> {\r\n    \r\n    \/\/ Convert Data to HexString mostly used in Encrypton Algos\r\n    public var hexString: String {\r\n        return self.toHexString()\r\n    }\r\n    \r\n    func toHexString() -> String {\r\n        let count = self.length \/ sizeof(UInt8)\r\n        var bytesArray = [UInt8](count: count, repeatedValue: 0)\r\n        self.getBytes(&bytesArray, length:count * sizeof(UInt8))\r\n        \r\n        var s:String = \"\";\r\n        for byte in bytesArray {\r\n            s = s + String(format:\"%02X\", byte)\r\n        }\r\n        return s;\r\n    }   \r\n\r\n\t\/\/ Return Swift Array from NSData\r\n    \r\n    \r\n    public func arrayOfBytes() -> [UInt8] {\r\n        let count = self.length \/ sizeof(UInt8)\r\n        var bytesArray = [UInt8](count: count, repeatedValue: 0)\r\n        self.getBytes(&bytesArray, length:count * sizeof(UInt8))\r\n        return bytesArray\r\n    }\r\n    \r\n    \/\/ Return array from NSData\r\n    class public func withBytes(bytes: [UInt8]) -> NSData {\r\n        return NSData(bytes: bytes, length: bytes.count)\r\n    }\r\n}<\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
Note:<\/b> NSData has an initializer that looks takes a bytes pointer: init(bytes: UnsafeMutablePointer , length: Int).<\/p>\n
You can read more about unsafe pointer parameters in Apple’s Interacting with C APIs<\/p>\n
NSFileManager\u00a0Extensions:<\/h3>\n
\n\n\n\n
\n
\/\/MARK: NSFileManager Extensions\r\n\r\nextension NSFileManager<\/span> {\r\n    class func documentsDirectory() -> String {\r\n        var paths = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true) as! [String]\r\n        return paths[0]\r\n    }\r\n    \r\n    class func cachesDirectory() -> String {\r\n        var paths = NSSearchPathForDirectoriesInDomains(.CachesDirectory, .UserDomainMask, true) as! [String]\r\n        return paths[0]\r\n    }\r\n}\r\n<\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
\n
Array Extensions:<\/h3>\n\n\n\n
\n
\/\/MARK: Array Extensions\r\nextension Array<\/span> {\r\n   \r\n    \/\/Array First Object\r\n    \r\n    func firstObject() -> T! {\r\n        var firstItem: T!\r\n        if !self.isEmpty {\r\n            firstItem = self[0]\r\n        }\r\n        return firstItem\r\n    }\r\n    \r\n    \/\/Array Last Object\r\n    \r\n    func lastObject() -> T! {\r\n        var lastItem: T!\r\n        if !self.isEmpty {\r\n            lastItem = self[self.count-1]\r\n        }\r\n        \r\n        return lastItem\r\n    }\r\n    \r\n    \r\n    \r\n    \/\/ Remove Object from Array similar to [ArrayObjec removeObject:(id)] in Objective-C\r\n\r\n    mutating func removeObject(object: U) -> Bool {\r\n        for (idx, objectToCompare) in enumerate(self) {\r\n            if let to = objectToCompare as? U {\r\n                if object == to {\r\n                    self.removeAtIndex(idx)\r\n                    return true\r\n                }\r\n            }\r\n        }\r\n        return false\r\n    }\r\n    \r\n    \/\/ Check Array contains Object similar to [ArrayObjec containsObject:(id)] in Objective-C\r\n    \r\n    func contains(obj: T) -> Bool {\r\n            return self.filter({$0 as? T == obj}).count > 0\r\n        }\r\n}\r\n\r\n<\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
NSObject Extensions:<\/h3>\n
\n\n\n\n
\n
\/\/ Perform selector after delay in swift\r\n\r\nextension NSObject<\/span> {\r\n    \r\n    func callSelectorAsync(selector: Selector, object: AnyObject?, delay: NSTimeInterval) -> NSTimer {\r\n        \r\n        var timer = NSTimer.scheduledTimerWithTimeInterval(delay, target: self, selector: selector, userInfo: object, repeats: false)\r\n        return timer\r\n    }\r\n}\r\n<\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
Localization String Extensions:<\/h3>\n
\n\n\n\n
\n
\/\/ localized string extension\r\n\r\nextension  String<\/span> {\r\n    var localized: String {\r\n        return NSLocalizedString(self, tableName:nil, bundle: NSBundle.mainBundle(), value: self, comment: \"\")\r\n    }\r\n}\r\n\r\n\r\n\/\/ localizing String with comment\r\n\r\nextension String<\/span>{\r\n    \r\n    func localizedStringWithComment(comment:String)-> String{\r\n        return NSLocalizedString(self, tableName: nil, bundle: NSBundle.mainBundle(), value: self, comment: comment)\r\n    }\r\n    \r\n}\r\n\r\nextension String<\/span>{\r\n    \r\n \/\/ MARK: Remove White Spaces\r\n\r\n    var condenseWhitespace:String{\r\n        return  self.stringByReplacingOccurrencesOfString(\" \", withString: \"\")\r\n    }\r\n}<\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
Integer Extensions:<\/h3>\n
\n\n\n\n
\n
\/\/ MARK: Integer Extensions\r\n\r\n\/\/Add space before Integer\r\nextension Int<\/span> {\r\n    func format(f: String) -> String {\r\n        return NSString(format: \"%\\(f)d\", self) as String\r\n    }\r\n}\r\n\r\n\/\/MARK: Double Extensions\r\n\r\n\/\/Add space before Double\r\nextension Double<\/span> {\r\n    func format(f: String) -> String {\r\n        return NSString(format: \"%\\(f)f\", self) as String\r\n    }\r\n}\r\n<\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
Source:<\/h1>\n
The Swift Programming Language: Extensions – Apple<\/a><\/h3>\n<\/div>\n","protected":false},"excerpt":{"rendered":"
What is Extension: Extensions are basically similar to an Objective-C category. Extensions are sort of methods adding in a Classe or Structure in a different flavour. Syntax of Extension: The syntax to create an extension is very similar to creating a type. You can write the following code in your Utils.swift class to add a […]<\/p>\n","protected":false},"author":169,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"iawp_total_views":15,"footnotes":""},"categories":[1400,1],"tags":[4848],"class_list":["post-25435","post","type-post","status-publish","format-standard","hentry","category-ios","category-technology","tag-ios"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t