如何在代码中定义列表视图模板 [英] How to define listview templates in code

问题描述

我正在编写一个复合控件，其中包含一个用于显示项目表的列表视图.通常在 Asp.NET 中使用 ListView 时，我会在代码转发中定义模板.

<布局模板><div class="ContentContainer"><div runat="server" id="itemPlaceholder"/>

</LayoutTemplate><项目模板><div><div><%#Eval("Content")%></div>

</ItemTemplate></asp:ListView>

我认为是这样的:

ListView view = new ListView();view.LayoutTemplate = .....view.ItemTemplate = .....//我什么时候调用这些?view.DataSource = myDataSource;视图.DataBind();

更新:我通过实现 ITemplate 接口创建了 2 个模板:

私有类 LayoutTemplate : ITemplate{public void InstantiateIn(控制容器){var external = new HtmlGenericControl("div");var inner = new HtmlGenericControl("div") { ID = "itemPlaceholder" };table.Rows.Add(row);container.Controls.Add(table);}}私有类 ItemTemplate : ITemplate{public void InstantiateIn(控制容器){var inner = new HtmlGenericControl("div");container.Controls.Add(inner);}}

我可以添加它们:

dataList.LayoutTemplate = new LayoutTemplate();dataList.ItemTemplate = new ItemTemplate();

但后来我卡住了，因为 container.DataItem 为空.

解决方案

诀窍是订阅 ItemTemplate 中 itemplaceholder 的数据绑定事件.

完整的解决方案:

公共类 FibonacciControl : CompositeControl{公共斐波那契控制(){//....}受保护的覆盖无效 CreateChildControls(){base.CreateChildControls();ListView view = new ListView();view.LayoutTemplate = new LayoutTemplate();view.ItemTemplate = new ItemTemplate();view.DataSource = FibonacciSequence();视图.DataBind();this.Controls.Add(view);}私有 IEnumerable斐波那契数列(){int i1 = 0;int i2 = 1;for (int i = 0; i < 迭代次数; i++){收益率收益 i1 + i2；int temp = i1 + i2;i1 = i2;i2 = 温度；}产量中断；}公共 int 迭代 { 获取；放;}私有类 LayoutTemplate : ITemplate{public void InstantiateIn(控制容器){var ol = new HtmlGenericControl("ol");var li = new HtmlGenericControl("li") { ID = "itemPlaceholder" };ol.Controls.Add(li);container.Controls.Add(ol);}}私有类 ItemTemplate : ITemplate{public void InstantiateIn(控制容器){var li = new HtmlGenericControl("li");li.DataBinding += 数据绑定；container.Controls.Add(li);}公共无效数据绑定(对象发送者，EventArgs e){var 容器 = (HtmlGenericControl)sender;var dataItem = ((ListViewDataItem)container.NamingContainer).DataItem;container.Controls.Add( new Literal(){Text = dataItem.ToString() });}}}

I am writing a Composite control, which contains a listview to display a table of items. Normally when using a ListView in Asp.NET I would define the templates in the code-forward.

<asp:ListView runat="server" ID="ArticleList">
    <LayoutTemplate>
        <div class="ContentContainer">
            <div runat="server" id="itemPlaceholder" />
        </div>
    </LayoutTemplate>
    <ItemTemplate>
        <div>
            <div><%# Eval("Content") %></div>
        </div>
    </ItemTemplate>
    </asp:ListView>

I assume it's something like:

ListView view = new ListView();
view.LayoutTemplate = .....
view.ItemTemplate = .....

// when do I call these?
view.DataSource = myDataSource;
view.DataBind();

Update: I created 2 templates by implementing the ITemplate interface:

private class LayoutTemplate : ITemplate
{
    public void InstantiateIn(Control container)
    {
        var outer = new HtmlGenericControl("div");
        var inner = new HtmlGenericControl("div") { ID = "itemPlaceholder" };
        table.Rows.Add(row);

        container.Controls.Add(table);
    }
}

private class ItemTemplate : ITemplate
{
    public void InstantiateIn(Control container)
    {
        var inner = new HtmlGenericControl("div");

        container.Controls.Add(inner);
    }
}

and I can add them using:

dataList.LayoutTemplate = new LayoutTemplate();
dataList.ItemTemplate = new ItemTemplate();

But then I get stuck, since container.DataItem is null.

解决方案

The trick is to subscribe to the databinding event of the itemplaceholder in the ItemTemplate.

The complete solution:

public class FibonacciControl : CompositeControl
{
    public FibonacciControl()
    {
        // ....
    }

    protected override void CreateChildControls()
    {
        base.CreateChildControls();

        ListView view = new ListView();

        view.LayoutTemplate = new LayoutTemplate();
        view.ItemTemplate = new ItemTemplate();

        view.DataSource = FibonacciSequence();
        view.DataBind();

        this.Controls.Add(view);
    }

    private IEnumerable<int> FibonacciSequence()
    {

        int i1 = 0;
        int i2 = 1;

        for (int i = 0; i < Iterations; i++)
        {
            yield return i1 + i2;
            int temp = i1 + i2;
            i1 = i2;
            i2 = temp;
        }
        yield break;
    }

    public int Iterations { get; set; }

    private class LayoutTemplate : ITemplate
    {

        public void InstantiateIn(Control container)
        {
            var ol = new HtmlGenericControl("ol");
            var li = new HtmlGenericControl("li") { ID = "itemPlaceholder" };
            ol.Controls.Add(li);

            container.Controls.Add(ol);
        }
    }

    private class ItemTemplate : ITemplate
    {
        public void InstantiateIn(Control container)
        {
            var li = new HtmlGenericControl("li");

            li.DataBinding += DataBinding;
            container.Controls.Add(li);
        }

        public void DataBinding(object sender, EventArgs e)
        {
            var container = (HtmlGenericControl)sender;
            var dataItem = ((ListViewDataItem)container.NamingContainer).DataItem;

            container.Controls.Add( new Literal(){Text = dataItem.ToString() });
        }
    }
}

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