# Validation

### ![](/files/t9SI1ERtisjPrFDZCqI9)

The first check mark next to the form widget is the validation rule. You can use this item to add a validation to your interaction page. When you add a validation rule you are prompted with the expression editor. Here you add the expression that should be validated. The validation rule overrides the ignore user input and will always be checked when leaving a node through a button exit. 

<table><thead><tr><th width="268">Property</th><th>Description</th></tr></thead><tbody><tr><td>Validation Rule</td><td>Expression that is checked for true or false when going out of the node with a button exit. This can be changed by selecting the input field or double clicking the expression in the template editor. </td></tr><tr><td>Style context</td><td>The color of the validation message box.</td></tr><tr><td>Show close button</td><td>Toggle the close (X) on or off. The close button is found on the right side of the validation message. (see image below) <br>This option is only visible on 4.2 runtime in staging or live.</td></tr></tbody></table>

<figure><img src="/files/J27B83pfkvjA9ygK5m2k" alt=""><figcaption><p>False validation for every style in the runtime as seen by a user.</p></figcaption></figure>

<figure><img src="/files/kNflbp9o4Xwb6QK3KXeB" alt=""><figcaption><p>Template editor</p></figcaption></figure>

<figure><img src="/files/lKnrqOGCxBT2VLJ5iqKG" alt=""><figcaption><p>Validation expression editor. The validation passes when this expression returns true. Example only lets you go through and leave the page when the subject has a value. When subject does NOT have a value the validation message is shown.</p></figcaption></figure>

{% hint style="info" %}
Check the [Ignore User Input information](/platform/wemmodeler/flowcharts.md#ignore-user-input) on how to prevent validation for a cancel action.
{% endhint %}


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