Inserting a non-breaking space in a @Html.DisplayFor when data is null or empty? ASP.Net MVC

Question

I have a need to insert a   via @HTML.DisplayFor when the backing model's value is null or empty.

I've tried using data annotations

 [DisplayFormat(ConvertEmptyStringToNull = true, NullDisplayText =" " ]
    public string  MiddleName { get; set; }

which does work to stick a " " where I expect it but I need to put a non-breaking space there instead.

Answer 1

Try something like:

var space = " ";

 [DisplayFormat(ConvertEmptyStringToNull = true, NullDisplayText ="@space" ]
public string  MiddleName { get; set; }

The issue with placing " " in that location is that it will be read as c# code. Instead, you want it to be read as HTML code at run time, and the above should achieve this.

Answer 2

这对我有用：

NullDisplayText = @" ", HtmlEncode = false

Answer 3

I worked around this problem by writing a helper instead of using @Html.DisplayFor . This is it.

@helper NonBreakingSpacesIfNullOrEmpty(string field, int spaces)
{
    if (String.IsNullOrEmpty(field))
    {
        @(new HtmlString(String.Concat(Enumerable.Repeat(" ", spaces))))
    }
    else
    {
        @field
    }
}

Your code would call it like this.

@FooHelper.NonBreakingSpacesIfNullOrEmpty(Model.MiddleName, 1)

Delete the spaces parameter and the associated logic if you don't need the repeat functionality.