Call a function after leaving input field

Question

On a contact form, I have several input fields. One of those fields, is an email address field:

<input type='text' name='input_email' onChange={this.validateEmail}/> 

Right now, I have the email validation function set to the onChange attribute. Thus, while the user is entering characters into the email field, an error message appears the whole time.

I want to change this, so that this.validateEmail only gets called once when the user leaves that specific input field. How would I accomplish this?

I can't find any default object events that would solve this issue.

FYI, using ReactJS

Answer 1

You can use onblur() or onfocusout(). It will call function once you click out of that text field.

Example:

function myFunction() {      var x = document.getElementById("sometext");      x.value = x.value.toUpperCase();  }

<input type="text" id="sometext" onfocusout="myFunction()">