# Selecting a file using regular expressions

Use the **Wildcard (RegExp)** field in the **File** tab to search for files by wildcard in the form of a regular expression. Regular expressions are more sophisticated than using `*` and `?` wildcards. This table describes several examples of regular expressions.

| File Name | Regular Expression          | Files Selected                                                                                  |
| --------- | --------------------------- | ----------------------------------------------------------------------------------------------- |
| `/dirA/`  | `.userdata.\.txt`           | Find all files in `/dirA/` with names containing userdata and ending with `.txt`                |
| `/dirB/`  | `AAA.\*`                    | Find all files in `/dirB/` with names that start with `AAA`                                     |
| `/dirC/`  | `\[ENG:A-Z\]\[ENG:0-9\].\*` | Find all files in `/dirC/` with names that start with a capital and followed by a digit (A0-Z9) |


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