ASP.NET MVC data annotation for currency format

Try using:

 [DisplayFormat(DataFormatString = "{0:C0}")]

Visit this post https://stackoverflow.com/a/19800496/3642086

Have you tried using DataType.Currency:

public class CostChart
{
    public string itemType { get; set; }
    [DataType(DataType.Currency)]
    public float? Cost{ get; set; }

}

Alternatively, you could use DataFormatString like this:

[DisplayFormat(DataFormatString = "{0:C0}")]`
public float? Cost{ get; set; }

But I prefer to set the display format with EditorFor. Here's a great tutorial on Extending Editor Templates for ASP.NET MVC tutorial.

That way, you write the display logic of your currencies in just ONE place, and you don't need to add that extract annotation every single time you want to display a currency amount.

--Edit

To make it work in EditorFor, you can also add ApplyFormatInEditMode = true to the end of the DataFormatString making the line as:

[DisplayFormat(DataFormatString = "{0:C0}", ApplyFormatInEditMode = true)]

try this :

public class CostChart
  {
    public string itemType { get; set; }

    [DataType(DataType.Currency)]
    public float? Cost{ get; set; }
  }

if you still do not see $ symbol, in web.config under write this line of code

<globalization culture ="en-us"/>

All right, when we talking about data annotations, there's two things to take in account:

The Data Annotation, which is:

[DisplayFormat(DataFormatString = "{0:C0}")]
public decimal? Cost{ get; set; }

And the tag in Razor pages, which is:

@Html.DisplayFor(model => model.Cost)

If you don't use "DisplayFor", data annotations is useless.

Another detail, if you want the decimal place, you should remove the last "0" after "C", as follow:

[DisplayFormat(DataFormatString = "{0:C}")]

Hope it helps you and good luck!