Question

I have a piece of MVC 2.0 html code is like below, I want replace it with MVC 3.0 Razor code, but I can not make it work using one line code like MVC 2.0.

<legend>&nbsp;Please add review for product :<%: Model.Product.ProductName.Length > 25 ? (string)Model.Product.ProductName.Substring(0, 25) + "..." : (string)Model.Product.ProductName %>&nbsp;<i style="color:Red">(&nbsp;<%: (string)Model.Product.Category.CategoryName %>&nbsp;)</i></legend>

The only way I can make it work is like below, but it looks not neat. I don’t like it, anyone can give me one line code which is worked in MVC 3.0 Razor will be great appreciate!!!

<legend>&nbsp;Please add review for product :
    <b>
        @{
            if(Model.Review.Product.ProductName.Length > 25)
            {
                @Model.Review.Product.ProductName.Substring(0, 25); @:...
            }
            else
            {
                @Model.Review.Product.ProductName;
            }
         }
    </b>
    &nbsp;<i style="color:Red">(&nbsp;@Model.Review.Product.Category.CategoryName&nbsp;)</i>&nbsp;</legend>

Answer 1

The ternary operator (x > y ? x : y) is usable in Razor. You just have to wrap it in brackets, so you can clean it up a lot by doing this (I’ve created a variable for product name for clarity’s sake):

@{ var productName = Model.Review.Product.ProductName; }
@(productName.Length > 25 ? productName.Substring(0, 25) + "..." : productName)

However, since what you’re doing is a fairly common task, you might want to think about creating an HTML helper method for the trimming:

public static class HtmlHelpers
{
    public IHtmlString Truncate(this HtmlHelper htmlHelper, string value, int maxLength)
    {
        if (htmlHelper == null)
            throw new ArgumentNullException("htmlHelper");

        return value != null && value.Length > maxLength
            ? new HtmlString(htmlHelper.Encode(value.Substring(0, maxLength)) + "…")
            : new HtmlString(htmlHelper.Encode(value));        
    }
}

Then you can just use: @Html.Truncate(Model.Review.Product.ProductName, 25) in your view, which is much cleaner.

You could also define an extension method on string:

public static class StringExtensions
{
    public void Truncate(this string value, int maxLength)
    {       
        return value != null && value.Length > maxLength
            ? value.Substring(0, maxLength) + "..."
            : value;
    }
}

which would allow you to just do this: @Model.Review.Product.ProductName.Truncate(25).