Access displayName attribute from the model in MVC

问题:

If my model have

[DisplayName("First Name")]
public string firstName { get; set; }

Then I can print it in the View with LabelFor

@Html.LabelFor(model => model.acc_first)

It will then render as

<label for="firstName">First Name</label>

• But how can I "raw" read the property (FirstName) attributes in the View? If for example, I want to send the value to a function on the View page

回答1:

@Html.DisplayNameFor(x => x.acc_first)

回答2:

To access the attributes you'll need a custom Html helper. Since the attributes aren't really part of the property or model you need to go in a round about way to access them.

public static IHtmlString DisplayName<TModel, TValue>(
                             this HtmlHelper<TModel> html,
                             Expression<Func<TModel, TValue>> expression) {
    var metadata = ModelMetadata.FromLambdaExpression<TModel, TValue>(expression, html.ViewData);

    return new HtmlString(metadata.DisplayName);
}

For additional attributes that aren't part of the DataAnnotations you can do the following:

Create a custom attribute

public class TooltipAttribute : Attribute, IMetadataAware {
    public TooltipAttribute(string tooltip) {
        this.Tooltip = tooltip;
    }

    public string Tooltip { get; set; }

    public void OnMetadataCreated(ModelMetadata metadata) {
        metadata.AdditionalValues["Tooltip"] = this.Tooltip;
    }
}

The magic happens in the OnMetadataCreated implementation. Here we can populate the AdditionalValues with anything we need for our particular Attribute. In this case we’re adding a Tooltip key. Your name should be unique as other attributes or providers may add their own keys with the same name It is important to remember that attributes are not always read in the same order. So your tooltip attribute may be called first, last or somewhere in the middle. This is an important distinction as it may cause undesired effects.

Then create a custom Attribute helper

public static IHtmlString TooltipFor<TModel, TValue>(
                             this HtmlHelper<TModel> html,
                             Expression<Func<TModel, TValue>> expression) {
    var metadata = ModelMetadata.FromLambdaExpression<TModel, TValue>(expression, html.ViewData);
    if (metadata.AdditionalValues.ContainsKey("Tooltip"))
        return new HtmlString((string)metadata.AdditionalValues["Tooltip"]);

    return new HtmlString("");
}

回答3:

You can access the value of the attribute Display(Name="...") in 4 steps:

var type = typeof(YourNamespace.Models.YourModelName);
var memInfo = type.GetMember("firstName"); // your member
var attributes = memInfo[0].GetCustomAttributes(typeof(System.ComponentModel.DataAnnotations.DisplayAttribute), false);
var displayname = ((System.ComponentModel.DataAnnotations.DisplayAttribute)attributes[0]).Name;

Then displayname will have the value First Name in your context.

回答4:

Building on Darren Oster's answer:

@Html.DisplayNameFor(x => x.acc_first)

Here's a link to the documentation for this: https://msdn.microsoft.com/en-us/library/system.web.mvc.html.displaynameextensions.displaynamefor(v=vs.118).aspx

You could use this in your view code like this:

@{ 
    var foo = Html.DisplayNameFor(x => x.acc_first);

    // call function
    DoStuff(foo);
}

回答5:

you should simply use

[Display(Name = "First Name")]


 public string name{ get; set; }

回答6:

@(This.Model.acc_first)

Should work

so in javascript you can use it like

function callme(val)
{
   //some ajax call with 
   @(This.Model.acc_first)
}

回答7:

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

should work for you. If not, try just

@Model.acc_first

Either one should work fine.