增加 String 转 NSDate 扩展方法

Author: klaus01

ruby-china-ios/Extensions/String+Ext.swift

@@ -0,0 +1,21 @@
+//
+//  String+Ext.swift
+//  ruby-china-ios
+//
+//  Created by 柯磊 on 16/10/9.
+//  Copyright © 2016年 ruby-china. All rights reserved.
+//
+
+import Foundation
+
+extension String {
+    func dateValue(format: String) -> NSDate? {
+        let dateFormatter = NSDateFormatter()
+        dateFormatter.dateFormat = format
+        return dateFormatter.dateFromString(self)
+    }
+    
+    func dateValueFromISO8601() -> NSDate? {
+        return self.dateValue("yyyy-MM-dd'T'HH:mm:ss.SSSZ");
+    }
+}