• 正则运算符定义
• 喵神提供的一段定义正则运算符(超级好用!!!),使用范例

if "onev@onevcat.com" =~
 "^([a-z0-9_\\.-]+)@([\\da-z\\.-]+)\\.([a-z\\.]{2,6})$" {
 println("有效的邮箱地址")
}
// 输出:
// 有效的邮箱地址

• 实现代码

struct RegexHelper {
    let regex: NSRegularExpression
    
    init(_ pattern: String) throws {
        try regex = NSRegularExpression(pattern: pattern,
                                        options: .CaseInsensitive)
    }
        func match(inputStr: String) -> Bool {
        let matches = regex.matchesInString(inputStr,
                                            options: [],
                                            range: NSMakeRange(0, inputStr.utf16.count))
        return matches.count > 0
    }
}

infix operator =~ {
associativity none
precedence 130
}

func =~(lhs: String, rhs: String) -> Bool {
    do {
        return try RegexHelper(rhs).match(lhs)
    } catch _ {
        return false
    }
}

• 下面是一些对String类的扩展(正则相关)
• 返回所有匹配到的字串集合,返回例如: [str1,str2,str3]

/**
 返回所有匹配到的字串集合
 - parameter pattern:  正则匹配规则
 - parameter inputStr: 要匹配的文本
 - returns:匹配到的字串集合
 */
func bl_regexWithPattern(pattern : String,
                         inputStr: String) -> [String] {
    // 使用正则表达式一定要加try语句
    do {
        // - 1、创建规则
        let pattern = pattern
        // - 2、创建正则表达式对象
        let regex = try NSRegularExpression(pattern: pattern, options: NSRegularExpressionOptions.CaseInsensitive)
        // - 3、开始匹配
        let res = regex.matchesInString(inputStr, options: NSMatchingOptions(rawValue: 0), range: NSMakeRange(0, inputStr.characters.count))
        // 输出结果
        var subStrArray = [String]()
        for checkingRes in res {
            let subStr = (inputStr as NSString).substringWithRange(checkingRes.range)
            subStrArray.append(subStr)
        }
        return subStrArray
    }
    catch {
        print(error)
    }
    //不匹配返回空串
    return [String]()
}

• 返回一个字典 key : 匹配到的字串, Value : 匹配到的字串
• 返回例如 : [ keyStr : [NSRange] ]

/// 返回一个字典  key : 匹配到的字串, Value : 匹配到的字串的Range数组
func bl_regexWithPatternAndRange(pattern : String,inputStr: String) -> [[String : [NSRange]]]? {
    let strArray = bl_regexWithPattern(pattern, inputStr: inputStr)
    
    var array = [[String : [NSRange]]]()
    for subStr in strArray {
        var dic = [String : [NSRange]]()
        let subStrRangeArray = bl_stringOfRangeArray(subStr, inputStr: inputStr)
        dic[subStr] = subStrRangeArray
        array.append(dic)
    }
    return array
}


/// 返回一个数组 Value : 匹配到的字串的Range数组
func bl_stringOfRangeArray(subStr : String, inputStr : String) -> [NSRange]? {
    
    guard inputStr =~ subStr else{
        return [NSMakeRange(0, 0)]
    }
    
    //设置Range数组
    var rangeArray = [NSRange]()
    
    //设置母串
    var bigString = inputStr
    // - 1、创建规则
    let pattern = subStr
    
    var count : Int = 0
    
    
    do{
        let regex = try NSRegularExpression(pattern: pattern, options: NSRegularExpressionOptions.CaseInsensitive)
        //获取子串个数
        count = regex.numberOfMatchesInString(bigString, options: .ReportProgress, range: NSMakeRange(0, bigString.characters.count))
        
    }catch{
        print(error)
    }
    
    
    for i in 0..<count {
        
        var subRange = (bigString as NSString).rangeOfString(pattern)
        
        let cutLoc = subRange.location + subRange.length
        let cutLen = bigString.characters.count - cutLoc
        
        bigString = (bigString as NSString).substringWithRange(NSMakeRange(cutLoc, cutLen))
        
        if i > 0 {
            let preSubRange = rangeArray[i - 1]
            subRange.location = preSubRange.location + preSubRange.length
        }
        rangeArray.append(subRange)
    }
    
    return rangeArray
}