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关于.net：如何在代码中定义列表视图模板

2023-04-17 03:46:00

How to define listview templates in code

我正在编写一个Composite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。

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我认为是这样的：

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

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

更新：
我通过实现ITemplate接口创建了2个模板：

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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);
}
}

我可以使用添加它们：

1 2	dataList.LayoutTemplate = new LayoutTemplate(); dataList.ItemTemplate = new ItemTemplate();

但是然后我被卡住了，因为container.DataItem为null。

诀窍是在ItemTemplate中订阅itemplaceholder的数据绑定事件。

完整的解决方案：

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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() });
}
}
}

此链接可能会有帮助吗？以编程方式使用模板控件

在设计时生成模板(以便将其保存在aspx文件中)有点棘手，但是DataBinding将自动工作。

这是一个基于Sonteks示例的示例，该示例创建一个模板，该模板包含随后使用数据绑定绑定的元素。

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public partial class View : PortalModuleBase
{
protected void Page_Load(object sender, EventArgs e)
{

}

#region MasterListView_ItemDataBound
public void MasterListView_ItemDataBound(object sender, ListViewItemEventArgs e)
{
ListViewItem objListViewItem = (ListViewItem)e.Item;
ListViewDataItem objListViewDataItem = objListViewItem as ListViewDataItem;

if (objListViewDataItem != null)
{
Tab objTab = (Tab)objListViewDataItem.DataItem;
IEnumerable<Tab> Tabs = CustomData(objTab.TabID);

Label TabIDLabel = (Label)objListViewItem.FindControl("TabIDLabel");
Label TabNameLabel = (Label)objListViewItem.FindControl("TabNameLabel");

TabIDLabel.Text = objTab.TabID.ToString();
TabNameLabel.Text = objTab.TabName;

AddListView(objTab.TabName, objListViewItem, Tabs);
}
}
#endregion

#region CustomData
static IEnumerable<Tab> CustomData(int? ParentID)
{
TabAdminDataContext objTabAdminDataContext = new TabAdminDataContext();

var myCustomData = from Tabs in objTabAdminDataContext.Tabs
where Tabs.ParentId == ParentID
select Tabs;

return myCustomData.AsEnumerable();
}
#endregion

#region AddListView
private void AddListView(string CurrentTabName, Control container, IEnumerable<Tab> ChildTabs)
{
// The Tab has Children so add a ListView
if (ChildTabs.Count() > 0)
{
ListView ChildListView = new ListView();
ChildListView.ID ="ChildListView";
ChildListView.ItemCommand += ListView_ItemCommand;
ChildListView.EnableViewState = true;
ChildListView.LayoutTemplate = new MyLayoutTemplate();
ChildListView.ItemTemplate = new MyItemTemplate();
ChildListView.DataSource = ChildTabs;
ChildListView.DataBind();

// Put the ListView in a Panel
var oTR = new HtmlGenericControl("tr") { ID ="ChildListViewTR" };
var oTD = new HtmlGenericControl("td") { ID ="ChildListViewTD" };

Panel objPanel = new Panel();
objPanel.ID ="ListViewPanel";
objPanel.ToolTip = CurrentTabName;
objPanel.Controls.Add(ChildListView);

oTD.Controls.Add(objPanel);
oTR.Controls.Add(oTD);
container.Controls.Add(oTR);
}
}
#endregion

#region ListView_ItemCommand
protected void ListView_ItemCommand(object sender, ListViewCommandEventArgs e)
{
LinkButton objButton = (LinkButton)sender;
Label1.Text = objButton.Text;
MasterListView.DataBind();
}
#endregion

#region MyLayoutTemplate
public class MyLayoutTemplate : ITemplate
{
public void InstantiateIn(Control container)
{
var oTR = new HtmlGenericControl("tr") { ID ="itemPlaceholder" };
container.Controls.Add(oTR);
}
}
#endregion

#region ItemTemplate
public class MyItemTemplate : ITemplate
{
public void InstantiateIn(Control container)
{
var oTR = new HtmlGenericControl("tr");

var oTD1 = new HtmlGenericControl("td");
LinkButton TabIDLinkButton = new LinkButton();
TabIDLinkButton.ID ="TabIDLinkButton";
oTD1.Controls.Add(TabIDLinkButton);
oTR.Controls.Add(oTD1);

var oTD2 = new HtmlGenericControl("td");
Label TabNameLabel = new Label();
TabNameLabel.ID ="TabNameLabel";
oTD2.Controls.Add(TabNameLabel);
oTR.Controls.Add(oTD2);

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

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

LinkButton TabIDLinkButton = (LinkButton)container.FindControl("TabIDLinkButton");
Label TabNameLabel = (Label)container.FindControl("TabNameLabel");

TabIDLinkButton.Text ="+" + objTab.TabID.ToString();
TabNameLabel.Text = objTab.TabName;

IEnumerable<Tab> ChildTabs = View.CustomData(objTab.TabID);

View objView = new View();
objView.AddListView(objTab.TabName, container, ChildTabs);
}

}
#endregion

}

设置一个类似的类：

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public delegate void InstantiateTemplateDelegate(Control container);

public class GenericTemplateImplementation : ITemplate
{
private InstantiateTemplateDelegate instantiateTemplate;

public void InstantiateIn(Control container)
{
this.instantiateTemplate(container);
}

public GenericTemplateImplementation(InstantiateTemplateDelegate instantiateTemplate)
{
this.instantiateTemplate = instantiateTemplate;
}
}

然后执行以下操作：

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view.LayoutTemplate = new GenericTemplateImplementation(p =>
{
p.Controls.Add(new Label { Text ="Foo" });
});

视图列表模板显示