如何为 DisplayFor() 创建 MVC Razor 模板

Question

I have a couple of properties in my view model that are display-only but I need to retrieve their values using jQuery to perform a calculation on the page. The standard Html.DisplayFor() method just writes their value to the page. I want to create a razor template that will allow me to render each element as:

<span id="ElementsId">Element's value</span>

I know I can specify a template in Html.DisplayFor() to use a particular template for rendering the property but within that template how do I identify the id attribute to write into the span tag?

@Html.DisplayFor(model => model.Element, "MyTemplate");

Answer 1

OK, I found it and it's actually very simple. In my Views\\Shared\\DisplayTemplates folder I have Reading.cshtml containing the following:

@model System.Int32
<span id="@ViewData.ModelMetadata.PropertyName">@Model</span>

This renders the correct tag using the name of the property as the id attribute and the value of the property as the contents:

<span id="Reading">1234</span>

In the view file this can be called using the following:

@Html.DisplayFor(model => model.Reading, "Reading")

Or if the model property is decorated with UIHint("Reading") then the template name can be left out of the call to DisplayFor() and it will still render using the template:

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

This should work equally well with custom editor templates.

Answer 2

I read many SO posts about defining template for @Html.DisplayFor for Boolean property but I couldn't clearly understand them. Your question is closed to this and after grasping it, I decided to add a new answer including all steps needed for implementing that. It might be helpful for other people.

1. Creating a template

At first, you need to add a Partial View in path below (the path is very important):

Views/Shared/DisplayTemplates/

For example, I created a Partial View that named _ElementTemplate and Fill it like this:

<span>
    @(@Model ? "Yes" : "No")
</span>

2. Adding UIHint to the Model

To make a connection between your property and template , you should add UIHint attribute like below in your model class:

[UIHint("_YesOrNoTemplate")]
public bool MyProperty { get; set; }

3. Using @Html.DisplayNameFor in View

In every view that you need this property, you can use code below:

<div>
    @Html.DisplayFor(modelItem => item.MyProperty)
</div>

Output

The code above is rendered to code below in my example ( if (MyProperty == true) ):

<div>
    <span>
        Yes
    </span>
</div>

Setting attributes

For setting id or other html attributes you can use ModelMetadata like this:

<span id="@ViewData.ModelMetadata.PropertyName">
    @(@Model ? "Yes" : "No")
</span>

Output with attribute

<div id="MyProperty">
    <span>
        Yes
    </span>
</div>

Answer 3

您可以将此id视图模型的一部分并在显示模板中使用它：

<span id="@Model.Id">@Html.DisplayFor(x => x.Value)</span>

Answer 4

有一篇文章解释了 Razor 中的Templates （显示 + 编辑器）以及UIHint属性。

Answer 5

I had exactly the same issue as the original post.

Not sure the last comment is valid. It would make the HTML id attribute a run-time value and therefore cannot be referenced with a design time name.

I used the overload of DisplayFor which allows you to add new objects onto the data dictionary (ViewBag)

My model is a C# object called Project with various properties. In my view I have this:

@Html.DisplayFor(model => model.ProjectName, "StringDisplaySetHtmlID", new { HtmlID = "project-name" })

This is using a custom template called StringDisplaySetHtmlID and the last parameter adds a key value pair to the Viewbag.

My template file looks like this:

@model string
<span class = "display-field" id = "@(ViewBag.HtmlID)">@Model</span> 

I'm also setting a class here for styling purposes. I've used the key name HtmlID rather than just ID to avoid a potential common naming collision.

Now in my javascript I can pick up the span's content using the following jquery:

var projectName = $('#project-name').text()

Answer 6

The best way to build a display template that will output the following:

<span id="ElementsId">Element's value</span>

Would be this:

<span id="@Html.IdForModel()">@Html.DisplayTextFor(m => m)</span>

These helpers may not have existed when this question was first posted, but this builds on David's answer in two ways:

1. Using @Html.DisplayTextFor(m => m) instead of @Model will still utilize data annotations while rendering the value instead of just essentially running ToString() on it.
2. Using @Html.IdForModel() instead of @ViewData.ModelMetadata.PropertyName would be preferable in cases where the model is nested or repeated, and the ID is not going to simply be the property name.