try catch throw prompt in javascript

One of the major advantages of JavaScript is its error-handling mechanism. The try-catch statement is used to handle the runtime errors that may occur during the execution of a piece of code. When an error occurs in the try block of a try-catch statement, it triggers the catch block, where the error can be handled.

The throw statement is used to throw a custom error message from the try block. It creates a new Error object and throws it to the catch block for handling. The throw statement is often used in conjunction with conditional statements to handle specific error scenarios.

The prompt function is an inbuilt function in JavaScript that displays a dialog box prompting the user for input. The prompt function takes two arguments: the message to display and the default value to display in the input field. If the user clicks the OK button, the value entered in the input field is returned. Otherwise, null is returned.

Here's an example of how to use try-catch, throw, and prompt together in JavaScript:

index.tsx
try {
  var age = prompt("Please enter your age:", "");
  if (age == null || age == "") {
    throw "Age must be filled out";
  }
  if (isNaN(age)) {
    throw "Age must be a number";
  }
  if (age < 18) {
    throw "You must be 18 or older to proceed";
  }
} catch (error) {
  alert("Error: " + error);
}
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In this example, the try block prompts the user for their age, and then checks if the age entered is valid. If the age is not valid, a custom error message is thrown using the throw statement. The catch block then displays the error message using the alert function.

This is just a simple example, but in real-world scenarios, error handling becomes critical as it can help prevent security vulnerabilities and ensure smooth running of your application.