Translate to razor Syntax from MVC 2.0 code

2019-03-01 01:16发布

问题:

I am trying to convert the popular asp.net MVC 2.0 solr.net sample app code to Razor syntax. I am not able to understand the last line ... Kindly help

 <% Html.Repeat(new[] { 5, 10, 20 }, ps => { %>
            <% if (ps == Model.Search.PageSize) { %>
            <span><%= ps%></span>
            <% } else { %>
            <a href="@Url.SetParameters(new {pagesize = ps, page = 1})">@ps</a>
            <% } %>
  <% }, () => { %> | <% }); %>

[update] Source for Html.Repeat extension

HtmlHelperRepeatExtensions.cs

回答1:

For this to work you will have to modify the Html.Repeat extension method to take advantage of Templated Razor Delegates as illustrated by Phil Haack. And then:

@{Html.Repeat(
    new[] { 5, 10, 20 }, 
    @<text>
        @if (item == Model.Search.PageSize)
        {
            <span>@item</span>
        }
        else
        {
            <a href="@Url.SetParameters(new { pagesize = item, page = 1 })">
                @item
            </a>
        }
    </text>,
    @<text>|</text>
);}

UPDATE:

According to your updated question you seem to be using a custom HTML helper but as I stated in my answer you need to updated this helper to use the Templated Razor Delegates syntax if you want it to work. Here's for example how it might look:

public static class HtmlHelperRepeatExtensions
{
    public static void Repeat<T>(
        this HtmlHelper html,
        IEnumerable<T> items,
        Func<T, HelperResult> render,
        Func<dynamic, HelperResult> separator
    )
    {
        bool first = true;
        foreach (var item in items)
        {
            if (first)
            {
                first = false;
            }
            else
            {
                separator(item).WriteTo(html.ViewContext.Writer);
            }

            render(item).WriteTo(html.ViewContext.Writer);
        }
    }
}

or if you want to have the helper method directly return a HelperResult so that you don't need to use the brackets when calling it:

public static class HtmlHelperRepeatExtensions
{
    public static HelperResult Repeat<T>(
        this HtmlHelper html,
        IEnumerable<T> items,
        Func<T, HelperResult> render,
        Func<dynamic, HelperResult> separator
    )
    {
        return new HelperResult(writer =>
        {
            bool first = true;
            foreach (var item in items)
            {
                if (first)
                    first = false;
                else
                    separator(item).WriteTo(writer);
                render(item).WriteTo(writer);
            }
        });
    }
}

and then inside your view:

@Html.Repeat(
    new[] { 5, 10, 20 }, 
    @<text>
        @if (item == Model.Search.PageSize)
        {
            <span>@item</span>
        }
        else
        {
            <a href="@Url.SetParameters(new { pagesize = item, page = 1 })">
                @item
            </a>
        }
    </text>,
    @<text>|</text>
)


回答2:

Possibly something like:

}, () => { <text>|</text> });