Sitecore Rich Text Validation - validation

Question

What's the best way of validating if a RTE Field has any content?
I've tried to add the expression "^(?!\s*$).+" to the validation but it doesn't work. This happens because RTE adds some html tags (that authors cannot see unless they switch for the HTML view) and the value of the field is actually not empty.

Answer 1

Rich Text fields could have a variety of empty tags for example by default Sitecore will replace line breaks with empty p tags. See HtmlEditor.LineBreak setting in Web.config:
<!-- HTML EDITOR LINE BREAK
Specifies the tag that the HTML editor inserts on Enter. Values can be
"br", "div" and "p".
-->
<setting name="HtmlEditor.LineBreak" value="p" />
Or only entering a whitespace will save the field value as <p> </p>
There are two approaches that could be considered.
The first is whether to worry about the different scenarios that the content editor could enter content into the rich text editor. The content editor may not be detailed about worrying about the markup and may decide to remove it leaving line breaks or whitespaces. You could handle the value from the fields by using HtmlAgilityPack to check if any nodes has inner text:
public bool HasContent(string val)
{
var htmlVal = new HtmlDocument();
htmlVal.LoadHtml(val);
if (htmlVal.DocumentNode == null || !htmlVal.DocumentNode.ChildNodes.Any())
return false;
return htmlVal.DocumentNode.ChildNodes.Any(x => !string.IsNullOrWhiteSpace(x.InnerText));
}
If nothing comes back, you would not render the value to the page eliminating possible empty p tags.
The second approach would be to create a custom validation rule. To complete this, you will need to create a field rule, the custom validator class and associating the validation rule on any rich text fields. Below are the steps:
Open Content Editor and navigate to sitecore/System/Settings/ValidationRules/Field Rules/Text and add "Validation Rule" named "No Content For Rich Text"
Fill out Title, Description and Type
Create RichTextValidator class under Web project under Validators folder
RichTextValidator.cs
using HtmlAgilityPack;
using Sitecore.Data.Validators;
using System;
using System.Linq;
using System.Runtime.Serialization;
namespace MyProject.Web.Validators
{
[Serializable]
public class RichTextValidator : StandardValidator
{
public RichTextValidator() { }
public RichTextValidator(SerializationInfo info, StreamingContext context) : base(info, context)
{ }
private bool HasContent(string val)
{
var htmlVal = new HtmlDocument();
htmlVal.LoadHtml(val);
if (htmlVal.DocumentNode == null || !htmlVal.DocumentNode.ChildNodes.Any())
return false;
return htmlVal.DocumentNode.ChildNodes.Any(x => !string.IsNullOrWhiteSpace(x.InnerText) && x.InnerText != " ");
}
protected override ValidatorResult Evaluate()
{
string contextText = this.ControlValidationValue;
if (!HasContent(contextText))
return ValidatorResult.CriticalError;
return ValidatorResult.Valid;
}
protected override ValidatorResult GetMaxValidatorResult()
{
return GetFailedResult(ValidatorResult.CriticalError);
}
public override string Name
{
get { return "Rich text contains no content."; }
}
}
}
On the data template field, add the validation rule
Finally, the rich text field should indicate a critical error when there is either just empty tags or <p> </p>