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1. Log into your Jira as Admin.
2. Go to Administration > Issues > Custom Fields page.
3. Click Add custom field and select Regular Expression Field.

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4. After you create the field, go to the corresponding Configure link. You will see the page like the following example:

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5. Click the Edit Regex link to configure the regular expression.

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6. Click the Save button and the regular expression will be associated to the current custom field.

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Using PCF - Regular Expression custom field

1. Go to an issue and edit the field with a value that does not match the regex.

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2. If you try to save the changes, an error message appears. Otherwise, here are some usage examples for this type of custom field.

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3. For more regex examples use the search from RegExLib.

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