# Check Regex Match

## Overview

This operation checks if a text conforms to a regular expression pattern. It serves as a conditional check, allowing you to perform additional operations depending on the truth of the statement.

## Syntax

This operation has two different formats. You can use either **is matched by** or **matches** to refer to the regular expression check.

#### 1. Option 1

```
the text is "{input}"
the regular expression is "{regex}"
if the text matches the regular expression then
 {action}
```

#### 2. Option 2

```
the text is "{input}"
the regular expression is "{regex}"
if the text is matched by the regular expression then
 {action}
```

## Data

The table below lists the names of the data elements in this operation and indicates which can be renamed in the syntax.

| Data Name              | Can Be Renamed |
| ---------------------- | -------------- |
| the text               | Yes            |
| the regular expression | No             |

## Parameters

**Parameters** are placeholders for data. Refer to the table below for details on each parameter in this operation. In the syntax, replace parameters with your own values.

<table><thead><tr><th width="110.765625">Parameter</th><th width="305.40234375">Description</th><th width="227.3203125">Examples</th><th>Required</th></tr></thead><tbody><tr><td><code>input</code></td><td>An input text to be checked against the regular expression.</td><td><ul><li>user123</li><li>Welcome to Kognitos.</li></ul></td><td>Yes</td></tr><tr><td><code>regex</code></td><td>A regular expression that defines the criteria the text must match.</td><td><ul><li>^[a-zA-Z0-9]+$</li><li>^\d3$</li></ul></td><td>Yes</td></tr><tr><td><code>action</code></td><td>An operation that occurs if <code>input</code> conforms to the regular expression.</td><td><ul><li>say "The username contains only letters and numbers."</li></ul></td><td>Yes</td></tr></tbody></table>

## Examples

#### 1. Validate Username Format

{% tabs %}
{% tab title="Automation" %}

<pre><code><strong>the username is "user123"
</strong>the regular expression is "^[a-zA-Z0-9]+$"
if the username matches the regular expression then
  say "The username contains only letters and numbers."
</code></pre>

{% endtab %}

{% tab title="Results" %}

```
The username contains only letters and numbers.
```

{% endtab %}
{% endtabs %}


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