# When to Use Control Flow Bricks

The following table describes scenarios where you might use each type of control flow brick:

| Scenario                                                                                                 | Control Flow Brick                         |                                                                                                                                                               |
| -------------------------------------------------------------------------------------------------------- | ------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| You need to run multiple bricks if a condition is met                                                    | If-Else                                    |                                                                                                                                                               |
| You need to run one brick(s) if a condition is met, and a different brick(s) if the condition is not met | If-Else                                    |                                                                                                                                                               |
| You are calling an API that sometimes fails                                                              | Retry                                      |                                                                                                                                                               |
| You want to wait for a condition to be met. For example: an API results to change                        | Retry                                      | In the Retry body, add a "Cancel Current Action" that runs if the condition has not been met yet (See Exceptions/Errors below)                                |
| You want to wait for an element to appear on the page                                                    | N/A - use the Wait for a DOM element brick | Trick question! The Wait for a DOM element brick has better performance because it can use native browser APIs to detect new elements                         |
| You want to show a custom error message/instructions to the user if a brick fails                        | Try-Except                                 | Leave the catch branch blank                                                                                                                                  |
| You want to ignore an error code when calling an API                                                     | Try-Except                                 | Leave the catch branch blank                                                                                                                                  |
| You want to perform an action for each item in a list of items returned from an API                      | For-Each                                   | <p>By default an element key is made available to the body <br><br>You can customize the name of the key provided to the body</p>                             |
| You want to preform an action for each element currently on the page that matches a selector             | For-Each Element                           | Current the Page Editor does not support selecting multiple elements. You must manually tweak the automatically generated selector to match multiple elements |


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