Syntax for ASP.Net MVC Phil Haack's Repeater s

问题:

I have recently started using ASP.Net MVC 3 RC 2 and have attempted to migrate an existing website in MVC 2 across using the Razor syntax. In the MVC 2 application I am using the code base repeater that Phil Haack kindly provided in the following: Phil Haack's Code Based Repeater

My question is around the syntax for Razor. I dont understand how the template in the following block can be rewritten in Razor and cannot find any documentation to help out (early days for documentation or my simplicity...):

<% Html.Repeater<ObjectToUse>(Model, "", "alt", (item, css) =>
   { %>
        <tr class="<%= item.Enabled ? css : "disabled" %>">
            <td><%= item.Name%></td>
            <td><%= item.Description%></td>
            <td><%= Html.RouteLink("Edit", item.ObjectToUseRouteValues("Edit"))%></td>
            <td></td>
            <td><%= Html.RouteLink("Select", item.ObjectToUseRouteValues())%></td>
        </tr>
<% }); %>

The problem comes when applying the template between the braces (the tr's). I have attempted using the WebGrid control, however it doesnt provide the functionality I require for setting a "disabled" row (I think).

回答1:

Actually, now that I think about it some more I don't think you can use Action parameters like that in Razor. I recall running into this before.

Updated

With answer from Andrew Nurse: "Unfortunately this is by design in the current parser, though I should note that we'd like to improve upon it. The issue is that markup is only valid at the start of a statement (which technically is where you've put it), but our C# "parser" is not intelligent enough to detect lambdas at the moment."

Though that might be out dated :)

@Html.Repeater(Model, "row", "row-alt", 
    @<tr class="@item.ClassType : "disabled"">
        <td>@item.Name</td>
        <td>@item.Description</td>
        <td>@Html.RouteLink("Edit", item.ObjectToUseRouteValues("Edit"))</td>
        <td></td>
        <td>@Html.RouteLink("Select", item.ObjectToUseRouteValues())</td>
    </tr>
)

    public static IHtmlString Repeater<T>(this HtmlHelper html, IEnumerable<T> items,
         string className, string classNameAlt, Func<T, HelperResult> render) {
        if (items == null)
            return new HtmlString("");

        int i = 0;
        StringBuilder sb = new StringBuilder();
        foreach (var item in items) {
            item.ClassType = item.Enabled ? (i++ % 2 == 0 ? className : classNameAlt) : "disabled";
            sb.Append(render(item).ToHtmlString());
        }

        return new HtmlString(sb.ToString());
    }

}

回答2:

I wrote @helper version. @helper do not use Generic method.

@helper ForEach(IEnumerable<int> items, Func<object, HelperResult> template){
    foreach(var item in items){
        Write(template(item));
    }
}
<div>
<ul>
@ForEach(Enumerable.Range(1,5),
    @<li>@item</li>
)
</ul>
</div>

hope this code.