The first element of a “try…catch…finally” block is the “try” clause. The “try” clause is used to limit a code block that can generate an exception and is compulsory for implementation. The “try” clause ought to be accompanied through one or each of the “catch” and “finally” clauses.
The “catch” block: The second element of “try…catch…finally” is the “catch” clause. The “catch” clause is a block of code that is most effective if an exception happens in the “try” clause. Although the “catch” clause is optional, it is not enough to deal with an exception without it. This is due to the fact that the “catch” clause stops the exception from propagating via the decision stack, permitting this system to recover. If an exception happens inside the “try” block, then it is handed over to the “catch” clause without much delay. The exception is passed off to the “catch” block for processing. The following instance shows how a “catch” clause is used to deal with a “ReferenceError”. Note that the “ReferenceError” item is included in the “catch” clause through the “exception” variable.
Complex programs can generate a few exceptions. In such cases, the “instanceof” operator may be used to distinguish among the various kinds of exceptions. In the example, expect that the “try” clause can generate various kind of exceptions. The corresponding “catch” clause uses “instanceof” to handle “TypeError” and “ReferenceError” exceptions one by one from all different kinds of errors.
The “finally” block: The last element of the “try…catch…finally” statement is optional, i.e. the “finally” clause. The “finally” clause is a block of code that is performed after the “try” and “catch” clauses, irrespective of any errors. The “finally” clause is beneficial for smoothing up the code (remaining files, etc). Note that the “finally” clause is even performed if an exception happens is not caught. In this type of scenario, the “finally” clause is performed after which the thrown exception proceeds normally.
The “finally” clause will be performed despite the fact that the “try” or “catch” clause executes a “return” announcement. For example, the subsequent characteristic returns fake because the “finally” clause is the last factor to execute.
The “throw” statement can be used with any type of data having a lot of benefits. Firefox gives debugging information for objects such as line number in the file where the exception occurred.
While the “throw” statement may be used with any statistics type, there are positive advantages to the use of the integrated exception types. Firefox, for instance, offers a unique remedy to the one’s gadgets via way of means of including debugging facts together with the filename and line number wherein the exception occurred.
- Identifiers and Keywords in TypeScript
- How to resolve unhandled exceptions in Node.js ?
- Exceptions Vs Errors in PHP
- PHP | Predefined Exceptions
- How to know which php.ini file is used ?
- How to detect which one of the defined font was used in a web page?
- How to handle the warning of file_get_contents() function in PHP ?
- How to handle badwords in Node.js ?
- How to handle the modal closing event in Twitter Bootstrap?
- How to handle errors in node.js ?
- How to handle events in dynamically created elements in jQuery ?
- How to handle states of mutable data types?
- How to handle multiple input field in react form with a single function?
- How to handle Child Threads in Node.js ?
- How cookies are used in a website?
- What are .extend and .prototype used for?
- 10 Node.js Framework to be used in 2019
- Why “chucknorris” is used as a color in HTML ?
If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to firstname.lastname@example.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.