Error Handling tutorial in Advance JavaScript

 <!DOCTYPE html>

<html lang="en">

<head>
    <meta charset="UTF-8">
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    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Error Handling Advance JavaScript</title>
    <link rel="stylesheet" href="">
</head>

<body>
    <script>
        // try-catch works Synchronously, try-catch is used for handle Error
        // Example 1 :
        // try {
        //     console.log("Start of Try");
        //     blabla();
        //     console.log("End of Try");
        // }
        // catch(error) {
        //     // console.log("Error has occurred.");
        //     console.log(error);
        // }

        // Example 2 : Below Code gives not correct output
        // try {
        //     setTimeout(function () {
        //         blabla;
        //     }, 1000);
        // }
        // catch (error) {
        //     console.log("Error has occurred.");
        // }

        // Example 3 : Proper usage of try-catch block with setTimeout() is as shown below :
        // setTimeout(function () {
        //     try {
        //         blabla;
        //     }
        //     catch (error) {
        //         console.log("Error has occurred.");
        //     }
        // }, 1000);

        // Example 4 :
        // try {
        //     blabla;
        // }
        // catch(error) {
        //     console.log(error.name);
        //     console.log(error.message);
        //     console.log(error.stack);
        // }

        // Example 5 :
        // try {
        //     blabla;
        // }
        // catch(error) {
        //     if(error instanceof ReferenceError) {
        //         console.log("ReferenceError");
        //     }
        //     else if(error instanceof TypeError) {
        //         console.log("TypeError");
        //     }
        //     else {
        //         console.log("Unknown Error");
        //     }
        // }

        // Example 6 :
        try {
            let json = `{
                "name": "Hello World",
                "age": 30
            }`;
            // JSON.parse() method converts JSON to JavaScript Object
            // JSON.stringify() method converts JavaScript Object to JSON
            let user = JSON.parse(json);

            if (!user.name) {
                throw new Error("Incomplete data : No name");
            }

            console.log(user.name);
            console.log(user.age);
        }
        catch (error) {
            console.log(error);
        }
        //  If "try" has Error OR "try" has not any Error but "finally" will always Execute as shown below :
        finally {
            console.log("Finally is Called.");
        }
    </script>
</body>

</html>



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