I know Sitecore Web Forms for Marketers module will be deprecated with Sitecore 9 release, with the introduction of Sitecore Forms module.
Nevertheless I thought to write a quick post on a recent simple issue that I had to try and find a solution for.
In one of my current projects, I had to add a length validation to Telephone field in WFFM form.
So, I just added another validation to Telephone field definition item in WFFM (see Image-1).
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Image-1 : Adding "count chars" validation to Telephone field |
Then I tested the form. Even thought validation worked, it was considering 0 as Minimum Length & 256 as Maximum Length of that field value. There were the default values define for Single-line text field class in Sitecore.
Even though we can see
Minimum Length &
Maximum Length fields for WFFM
Single-line text field (see in image-2), WFFM Design interface for
Telephone field does NOT display any
Minimum Length &
Maximum Length field (see image-3).
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Image-2 : WFFM Single-line Text Field Design Interface |
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Image-3 : WFFM Telephone Field Design Interface |
But, If you look at the Telephone field definition in WFFM (see Image-4), you can see it is using "Sitecore.Forms.Mvc.ViewModels.Fields.TelephoneField,Sitecore.Forms.Mvc".
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Image-4 : Telephone Field Definition Item |
So, once I looked into the code base for that class by decoding the Sitecore.Forms.Mvc.dll, I could see it was extending the Single-line text field class (see Image-5)
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Image-5 : TelephoneField Class |
So, as you know, SingleLineTextField is created to use Maximum Length & Minimum Length properties.
Finally, to get these length validations to work, all I had to do is add following parameters to "Parameters" field of that Telephone field item (see Image-6)
<MinLength>10</MinLength><MaxLength>15</MaxLength>
That was it. After that, Telephone field validation works as I needed with 10 characters as Minimum Length and 15 characters as Maximum length.
Hope this helps to someone ! :-)