ASP.NET MVC中的级联DropdownList [英] Cascading DropdownList in ASP.NET MVC

问题描述

如何在ASP.NET MVC中将值绑定到DropdownList？

How to Bind Values To DropdownList in ASP.NET MVC?

推荐答案

在行动中：

In Action :

public ActionResult Create()
    {
        var db = new DbDataContext();
        IEnumerable<SelectListItem> states = db.States.Select(p => new SelectListItem
        {
            Value = p.StateId.ToString(),
            Text = p.Name
        });
        ViewData["YourData"] = states;
        return View();
    } 

查看：

In View :

<div class="editor-field">
                <%: Html.DropDownListFor(model => model.StateId, (IEnumerable<SelectListItem>)ViewData["YourData"])%>
                <%: Html.ValidationMessageFor(model => model.StateId) %>
            </div>

首先，有没有像ASP.NET MVC中的数据绑定那样的东西。您必须使用视图模型或ViewBag（或ViewData，如果您仍使用MVC2）将控制器中的选择值传递给模型。这是一个很好的howto： http：// www。 mikesdotnetting.com/Article/128/Get-The-Drop-On-ASP.NET-MVC-DropDownLists [ ^ ]，但Google可以为您提供更多信息。

现在有级联。

有几种方法，但这些方法很有趣：

1）如果你知道你的所有列表首先渲染你的页面，你可以将它们作为JS数组嵌入到视图中，并在客户端过滤它们 - 这不是动态的，可能是一个巨大的开销。

2）嵌入你的级联逻辑进入视图： MVC级联Ajax的简单实现下拉 [ ^ ]，但我不推荐这个，因为它不遵循MVC概念。

3）使用Jquery，制作一个ajax回调来填充第二个（及以下） ）列表。我找到了一个插件，您可以使用： http://weblogs.asp.net/rajbk/archive/2010/05/20/cascadingdropdown-jquery-plugin-for-asp-net-mvc.aspx [ ^ ] - 我推荐这种方法，因为你可以动态地计算要放入列表的元素，并且你不需要刷新页面。

First of all, there is no such thing as data binding in ASP.NET MVC. You have to pass select values from the controller to the model either using a view model, or via ViewBag (or ViewData if you still use MVC2). Here is a good "howto": http://www.mikesdotnetting.com/Article/128/Get-The-Drop-On-ASP.NET-MVC-DropDownLists[^], but google can give you more.
And now with cascading.
There are several approaches, but these can be interesting:
1) If you know all your lists on the first render of your page, you can embed them in the view as JS arrays, and filter them on client side - this is not dynamic and can be a huge overhead.
2) Embed your "cascading" logic into the view: Simple Implementation of MVC Cascading Ajax Drop Down[^], but I don't recommend this, because it is not following the MVC concepts.
3) Using a Jquery, making an ajax callback to populate the second (and following) lists. I found a plugin, you might use: http://weblogs.asp.net/rajbk/archive/2010/05/20/cascadingdropdown-jquery-plugin-for-asp-net-mvc.aspx[^] - I reccomend this approach, since you can dinamically calculate what elements to put into the list, and you don't need to refresh the page.

检查asp中级联下拉列表的清晰解决方案.net mvc：



http://blogs.msdn.com/b/rickandy/archive/2012/01/09/cascasding-dropdownlist-in-asp-net- mvc.aspx？CommentPosted = true＃commentmessage [ ^ ]

check for clear solution of cascading dropdownlist in asp.net mvc:

http://blogs.msdn.com/b/rickandy/archive/2012/01/09/cascasding-dropdownlist-in-asp-net-mvc.aspx?CommentPosted=true#commentmessage[^]

这篇关于ASP.NET MVC中的级联DropdownList的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！