工作随笔——Swift中的Range和一些字符操作

        //截取子串
        let str = "Hello,Swift"
        let startIndex = str.startIndex
        //方法一：使用advancedBy + stringByReplacingCharactersInRange
        let endIndexA = startIndex.advancedBy(str.characters.count-1)
        let rangeOfHelloA = Range(start: startIndex, end: endIndexA)
        let newStr = str.stringByReplacingCharactersInRange(rangeOfHelloA, withString: "")
        print("newStr1 = " + newStr)
        
        //方法二：advancedBy + subStringWithRange
        let newStr2 = str.substringWithRange(rangeOfHelloA)
        print("newStr2 = " + newStr2)
        
        //方法三：使用NSString类型；Swift也提供了NSString和S挺
        let str_OC = str as NSString
        let newStr3 = str_OC.substringWithRange(NSRange(location: 0, length: 5)) as String
        //或者
//        let newStr3 = str_OC.substringWithRange(NSMakeRange(0, 5)) as String
        print("newStr3 = " + newStr3)
        
        
        //插入字符
        var originStr = "0000"
        originStr.insert("5", atIndex: originStr.startIndex.advancedBy(2))
        print("newstr4 = " + originStr)
        //插入字符串->字符串需要转成字符集才能进行操作
        originStr.insertContentsOf("字符串".characters, at: originStr.startIndex.advancedBy(2))
        print("newStr5 = " + originStr)
        
        //移除其中的某个字符
        var originStr2 = "12345"
        originStr2.removeAtIndex(originStr2.startIndex)
        print("newStr6 = " + originStr2)
        //移除子串  注意：endIndex是从整个字符的后一位开始的，直接使用originStr2.endIndex会导致越界；
        let removeRange = originStr2.startIndex.advancedBy(1)...originStr2.endIndex.advancedBy(-2)
        originStr2.removeRange(removeRange)
        print("newStr7 = " + originStr2)