JavaScript exception handling

When the JavaScript engine executes the code, various errors occur, and the various error-handling statements are shown in table 1:

Statement	Description
Try	Statement to test code block errors
Catch	Statement Handling Errors
Throw	Statement to create a custom error

1. Many of the errors in the code are sometimes not completely avoided, at which point a manual prompt or interrupt program is required, and the current error is captured. JavaScript itself will automatically throw errors in syntax or spelling, and to manually catch these errors, you need to use the Try...catch statement.

• A try statement defines a block of code that performs an error test at execution time.
• A catch statement defines a block of code that executes when a try statement has an error.

  Try   {// Run code here   }catch(err)  {///  Handling errors here   }

  2.throw statement: The throw statement allows the developer to create a custom error, term: Create or throw an error (exception). If you use the throw statement with try and catch, you can program the flow and generate custom error messages. Throw statement:

• Throw exception
• An exception can be a JavaScript string, a number, a logical value, or an object.

JavaScript exception handling