Magento2: How can I create a validation for telephone inputs inside Magento Admin?

Question

I have to create a validation for the telephone inputs in Magento Admin. I need to set a min of characters like 8 and a max of 15. I'm currently using 2.2.8 version.

I tried to set the validation by admin using telephone attribute, but it didn't work. It inserts a class for validation but doesn't validate at all.

Thanks!

• Mohit Rane: do you want this validation in system.xml file or in custom form?
• Mariana Martins Menezes: Hi @MohitRane, I want it for the new customer form and billing and shipping form inside the admin, but I don't even know where to look. =(
• Mohit Rane: do you want this change in custom module functionality or you to want to change in Magento's default functionality?
• Mariana Martins Menezes: Hey @MohitRane, I want to change in Magento's default functionality.
• Mohit Rane: can you share the screenshot of where you want this validation to make sure we're talking about the same thing?

Answer 1

Put the following code inside the telephone number block in your layout file

 <item name="validation" xsi:type="array">
 <item name="min_text_length" xsi:type="number">8</item>
 <item name="max_text_length" xsi:type="number">15</item>
 <item name="validate-number" xsi:type="number">0</item>
 </item>