CODEWITHSUNDEEP
c#.netasp.net-mvc
Refracted Paladin
Refracted Paladin

Reputation: 12216

How can I truncate a string using MVC Html Helpers?

I am trying to truncate a long string for display only on my index page. It is shown like so:

<td>
    @Html.DisplayFor(modelItem => item.Description)
</td>

The Description can be 500 characters long but I can't show that much on that grid layout. I'd like to show just the first 25 as they can see all of it on the Details page but I cannot seem to get it to work with out truncating it at the model level.

Something like this would be nice:

@Html.DisplayFor(modelItem => item.Description.Take(25))
@Html.DisplayFor(modelItem => item.Description.Substring(0,25)

EDIT

I'm getting the following exception at Runtime when I try either method.

Templates can be used only with field access, property access, single-dimension array index, or single-parameter custom indexer expressions.

Upvotes: 8

Views: 18263

Answers (7)

dev-siberia
dev-siberia

Reputation: 2865

The HTML helper for ASP Net Core 3 MVC.

public static HtmlString Truncate(this IHtmlHelper helper, string text, int maxLength = 100)
{
    if (text == null) return new HtmlString("");

    if (text.Length > maxLength)
    {
        text = text.Substring(0, maxLength) + "...";
    }
    return new HtmlString($"{text}");
}

Use in cshtml file

@Html.Truncate(item.Description)

Or you can use param

@Html.Truncate(item.MusicUrl, 50)

Upvotes: 1

user3590235
user3590235

Reputation: 173

Try this if you want to use the HTML helpers. Say you want to get part of a string before the first space .IndexOf(' ') (or you can just use a predefined index 25 like u said):

@Html.DisplayFor(modelItem => item.Description).ToString().Substring(0,item.Description.IndexOf(' '))

Upvotes: 1

Yarag
Yarag

Reputation: 1

Try an extension

public static string TruncateMiddle(this string value, int lengthExpected, string separator = "...")
    {
        if (value.Length <= lengthExpected) return value;

        decimal sepLen = separator.Length;
        decimal charsToShow = lengthExpected - sepLen;
        decimal frontChars = Math.Ceiling(charsToShow / 2);
        decimal backChars = Math.Floor(charsToShow / 2);

        return value.Substring(0, (int)frontChars) + separator + value.Substring(value.Length - (int)backChars);            
    }

Use

MyLongString.TruncateMiddle(50)

Return something like this: Lorem ipsum dolor sit ame...onsectetur cras amet.

Upvotes: 0

arserbin3
arserbin3

Reputation: 6148

you could either truncate the data before it gets to the View, or use this Razor:

@{
    var shortDescript = String.Concat(modelItem.Take(25));
}
@Html.DisplayFor(modelItem => shortDescript)

Upvotes: 4

Mike Cheel
Mike Cheel

Reputation: 13106

You might consider creating a special model property for such instances where you need this: 

public class MyModel
{
    public string MyDescription {get; set;}
    public string MyShortDescription {
        get 
        {
              return Truncate(MyDescription, 25);
        }
}

private string Truncate(string, howMany)
{
   // Code to perform the substring here
}

@Html.DisplayFor(modelItem => item.MyShortDescription);

Upvotes: 1

48klocs
48klocs

Reputation: 6103

You could do this with an extension method.

public static string Truncate(this string source, int length)
{
    if (source.Length > length)
    {
        source = source.Substring(0, length);
    }

    return source;
}

Then in your view:

@item.Description.Truncate(25)

Upvotes: 7

Nathan A
Nathan A

Reputation: 11319

Don't use the html helper. Just do this:

@item.Description.Substring(0, Math.Min(item.Description.Length, 25));

I'm assuming you are in some loop where item is the current element.

Upvotes: 29

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