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VOOZH | about |
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VOOZH | about |
JavaScript Promise catch() method is called whenever a promise is rejected. This method itself returns a promise so it can also be used to chain promises. This method is used for error handling. This method is mainly used after .then to chain a promise and handle reject condition. This method internally calls .then with undefined and rejected conditions as arguments.
Syntax:
catch(()=>{})
Parameter: This method takes a callback function that decides what action to perform when the promise is rejected
Return Type: This method returns a promise which is in the pending state even if the previous promise is finished.
Example 1: This example uses the catch method to handle the reject condition of a promise.
Output: Since the promise returns a reject it moves to the catch method where the rejected value is received and printed on the console.
Failure
Example 2: This example specifies a condition where the catch method fails to catch an error.
Output: Normally this error should be caught by the catch block but since the error is thrown by an asynchronous function the catch block fails to handle it.
Example 3: This method explains the condition when the catch method will not be called.
Output: The catch method is not called as the promise is resolved so only then the method is called.
Equal Values
Supported Browsers:
We have a complete list of Javascript Promise methods, to check those please go through the article.
