javascript try catch 練習

javascript try catch 

CH 1-14

<script>
    function UserException(message) {
        this.message = message;
        this.name = "UserException";
    }

    UserException.prototype.toString = function() {
        return this.name + ': "' + this.message + '"';
    }

    try {

        var empcode = prompt(" 1.字串 \n 2.數字型態 \n 3.布林 \n 4.物件 \n 5.error", "");
        if (empcode == "1") {
            throw "err_1";
        } else if (empcode == "2") {
            throw 2;
        } else if (empcode == "3") {
            throw true;

        } else if (empcode == "4") {
            throw new UserException("user value too hight");

        } else if (empcode == "5") {
            throw new Error("error")
        }

    } catch (e) {
        if (e == "err_1") {
            console.log("1.字串");
        } else if (e == 2) {
            console.log("2.數字");
        } else if (e == true) {
            console.log("3.布林");
        } else if (e.name == "UserException") {
            console.log("4.自定義物件");
            //二種寫法
            console.log("第一種寫法  " + "name:" + e.name + " message:" + e.message);
            console.log("第二種寫法  " + e.toString());
        } else {
            console.log("5.ERROR物件");
            console.log(e.name + " " + e.message)
        }

    } finally {

    }
</script>

相關參考: http://www.javascriptkit.com/javatutors/trycatch2.shtml

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