Swift: 从一定格式的字符串中截取数据返回(正则表达式方式)

A.    输入要截取的字符串，返回一个目标输出参数的字符串数组

1.输入输出参数：

  1. input str = "raw=281804 mV level=100.00%"

  2. output battaryArray[0] = "281804"

            battaryArray[1] = "100.00%";

2.方法实现：

    /// getBatteryParamsFromString---->[String]
    /// # getBatteryParams:
    ///          1. batteryValue  2. batteryLevel
    /// # example:
    ///          1. input str = "raw=281804 mV level=100.00%"
    ///          2. output battaryArray[0] = "281804"
    ///                    battaryArray[1] = "100.00%";
    ///
    /// - Parameter str: String
    /// - Returns: [String]
    private func getBatteryParams(str: String) -> [String]{
        var batteryArray = [String]()
        let batteryValueKey = "raw="
        let batteryLevelKey = "level="
        let substringArry = (str as NSString).components(separatedBy: " ");
        assert(substringArry.count > 0, "Get the BatteryParams Fail")
        for sub:String in substringArry {
            //print(sub);
            let substring = (sub as NSString).contains(batteryValueKey)
            if substring {
                batteryArray.append((sub as NSString).substring(with: NSMakeRange(batteryValueKey.count, sub.count-batteryValueKey.count)))
            }else {
                if sub.contains(batteryLevelKey) {
                    batteryArray.append((sub as NSString).substring(with: NSMakeRange(batteryLevelKey.count, sub.count-batteryLevelKey.count)))
                }
            }
        }
        return batteryArray
    }

B.    输入要截取的字符串，返回一个目标输出参数的Float数组(正则表达式)

1.输入输出参数：

  1. input str = "raw=281804 mV level=100.00%"

    swift 中对应的正则表达式"raw=(\\d+) mV level=(\\d+(?:\\.\\d+)?)%"

  

2. output battaryArray[0] = "281804"

            battaryArray[1] = "100";

2.方法实现：

    /// getBatteryParamsFromString---->[Float]
    /// # getBatteryParams:
    ///          1. batteryValue  2. batteryLevel
    /// # example:
    ///          1. input str = "raw=281804 mV level=100.00%"
    ///          2. output battaryArray[0] = "281804"
    ///                    battaryArray[1] = "100";
    ///
    /// - Parameter str: String
    /// - Returns: [Float]
    private func getBatteryParams(str: String) -> [Float]{
        let regex = try! NSRegularExpression(pattern: "raw=(\\d+) mV level=(\\d+(?:\\.\\d+)?)%", options: [])
        let matches = regex.matches(in: str, options: [], range: NSRange(str.startIndex..., in: str))

        assert(matches.count > 0, "Get the BatteryParams Fail")

        var resultArray: [String] = []
        for match in matches {
            //            let str1 = String(str[Range(match.range(at: 1), in: str)!])
            //            let str2 = String(str[Range(match.range(at: 2), in: str)!])
            //            resultArray.append(str1)
            //            resultArray.append(str2)
            resultArray.append(contentsOf: [String(str[Range(match.range(at: 1), in: str)!]),                                                                          String(str[Range(match.range(at: 2), in: str)!])])
        }

        let result: [Float] = resultArray.map({Float($0)!})
        return result
    }