I am using symfony v2.3 and was trying to validate if a field in my twig form is null or undefined. Here is my twig form:
{{form_start(form)}}
<p>
Date
{{form_widget(form.date)}}
</p>
<p>
School
{{form_widget(form.school)}}
</p>
<p>
City
{{form_widget(form.city)}}
</p>
<p>
Name
{{form_widget(form.name)}}
</p>
<p>
{{ form_widget(form.save)}}
</p>
{{form_end(form)}}
I tried researching about it and found something interesting but i dont know how to do it when i am using a twig for my form. How to determine if variable is 'undefined' or 'null'? I want to do something like this but i dont know how.
if(typeof variable_here === 'undefined'){
// your code here.
};