Asp.NET ListView Data Control Dynamically Databind

Question

I am trying to implement a ListView data control for displaying and editing lookup table/ application level variables. There are multiple entity classes which can be bound to the ListView, so the ItemTemplate needs to be dynamically bound to the selected entity object.

For example i have:

AddressType { AddressTypeId, AddressTypeDescription}, 
PhoneType { PhoneTypeId, PhoneType}, 
MarriageStatusType { MarriageStatusId, marriageStatusType}

Those generated entity objects prevent me from simply doing something like the following snippet, because the ID and Type properties are different on each business object.

<ListView>
...

<itemTemplate>
    <tr> 
       <td runat="server" id="tdId"> <%# Eval("ID") %> </td> 
       <td runat="server" id="tdType"> <%# Eval("TypeNameDescription") %> </td> 
    </tr>
</itemTemplate>

...
</ListView>

I am trying to discover : 1. How to iterate over the ListView Items to insert the appropriate property value into the server side html td tags. 2. How to use Databinder.Eval on the ListView items to insert that property value.

Thanks in advance!

Answer 1

Ok, I find way to render repeater inside the listview, I don't know if I can paste the whole code because it is pretty long. the result html like following:

 

   
time1               
                         [comment: following is repeater inside listview]
   scenarioNamegroupName1groupName2
   S1g1Conc1g2Conc1
   S2g1Conc2g2Conc2
   S3g1Conc1g2Conc3
   
   

   
time2
                         [comment: following is repeater inside listview]
   scenarioNamegroupName1groupName2
   S1g1Conc1g2Conc1
   S2g1Conc2g2Conc2
   S3g1Conc1g2Conc3
   
   

   
time3
                         [comment: following is repeater inside listview]
   scenarioNamegroupName1groupName2
   S1g1Conc1g2Conc1
   S2g1Conc2g2Conc2
   S3g1Conc1g2Conc3
   
   
 

The hard part is that the number of group can be different

my aspx page like following:

...hm...the forum I cannot use verbatim for code, the pre block won't work for some character

 KeyValuePair<string, List<scenarioItem>> myData = (KeyValuePair<string, List<scenarioItem>>)(((System.Web.UI.WebControls.ListViewDataItem)(e.Item)).DataItem);
    Repeater repeater = (Repeater)e.Item.FindControl("childData");
    repeater.HeaderTemplate = new MyTemplate(ListItemType.Header);
    repeater.ItemTemplate = new MyTemplate(ListItemType.Item);
    repeater.AlternatingItemTemplate =
       new MyTemplate(ListItemType.AlternatingItem);
    repeater.FooterTemplate = new MyTemplate(ListItemType.Footer);
    repeater.DataSource = myData.Value;
    repeater.DataBind();



public class MyTemplate : System.Web.UI.ITemplate

{ System.Web.UI.WebControls.ListItemType templateType; public MyTemplate(System.Web.UI.WebControls.ListItemType type) { templateType = type; }

static void Item_DataBinding(object sender, System.EventArgs e)
{
    PlaceHolder ph = (PlaceHolder)sender;
    RepeaterItem ri = (RepeaterItem)ph.NamingContainer;
    scenarioItem myDataItem = (scenarioItem)ri.DataItem;

    if (ri.ItemIndex == 0) { 
        //create the header column part once
        //Add ScenarioName
        ph.Controls.Add(new LiteralControl("<tr><td>ScenarioName</td>"));

        //Add group concentration part
        foreach (recGroupConcItem concItem in myDataItem.mGroupConcList)
        {
            ph.Controls.Add(new LiteralControl("<td>" + concItem.groupName + @"</td>"));
        }
        ph.Controls.Add(new LiteralControl("</tr>"));

    }

    //Add ScenarioName
    ph.Controls.Add(new LiteralControl("<tr><td>"+myDataItem.scenarioName+@"</td>"));

    //Add group concentration part
    foreach (recGroupConcItem concItem in myDataItem.mGroupConcList) {
        ph.Controls.Add(new LiteralControl("<td>" + concItem.groupConc.ToString() + @"</td>"));
    }
    ph.Controls.Add(new LiteralControl("</tr>"));
}

static void ItemAlt_DataBinding(object sender, System.EventArgs e)
{
    PlaceHolder ph = (PlaceHolder)sender;
    RepeaterItem ri = (RepeaterItem)ph.NamingContainer;
    scenarioItem myDataItem = (scenarioItem)ri.DataItem;

    //Add ScenarioName
    ph.Controls.Add(new LiteralControl("<tr bgcolor=\"lightblue\"><td>" + myDataItem.scenarioName + @"</td>"));

    //Add group concentration part
    foreach (recGroupConcItem concItem in myDataItem.mGroupConcList)
    {
        ph.Controls.Add(new LiteralControl("<td>" + concItem.groupConc.ToString() + @"</td>"));
    }
    ph.Controls.Add(new LiteralControl("</tr>"));
}

static void ItemHeader_DataBinding(object sender, System.EventArgs e)
{
    PlaceHolder ph = (PlaceHolder)sender;
    RepeaterItem ri = (RepeaterItem)ph.NamingContainer;
    scenarioItem myDataItem = (scenarioItem)ri.DataItem;

    //Add ScenarioName
    ph.Controls.Add(new LiteralControl("<tr><td>ScenarioName</td>"));

    //Add group concentration part
    foreach (recGroupConcItem concItem in myDataItem.mGroupConcList)
    {
        ph.Controls.Add(new LiteralControl("<td>" + concItem.groupName + @"</td>"));
    }
    ph.Controls.Add(new LiteralControl("</tr>"));
}


public void InstantiateIn(System.Web.UI.Control container)
{
    PlaceHolder ph = new PlaceHolder();
    Label item1 = new Label();
    Label item2 = new Label();
    item1.ID = "item1";
    item2.ID = "item2";

    switch (templateType)
    {
        case ListItemType.Header:
            ph.Controls.Add(new LiteralControl("<table border=\"1\">"));
            //    "<tr><td><b>ScenarioName</b></td>" +
            //    "<td><b>Group1</b></td> <td><b>Group2</b></td> <td><b>Group3</b></td> <td><b>Group4</b></td> </tr>"));
            //ph.DataBinding += new EventHandler(ItemHeader_DataBinding);
            break;
        case ListItemType.Item:
            ph.DataBinding += new EventHandler(Item_DataBinding);
            break;
        case ListItemType.AlternatingItem:
            ph.DataBinding += new EventHandler(ItemAlt_DataBinding);
            break;
        case ListItemType.Footer:
            ph.Controls.Add(new LiteralControl("</table>"));
            break;
    }
    container.Controls.Add(ph);
}

}

Answer 2

Ok in answer to your questions:

• You can iterate over the ListViewItems by using the OnItemDataBound event in the parent ListView. You can then use this to databind nested child ListViews (or insert Html or manipulate the contents of the list in any way you need). Make sure you use ListViewItemEventArgs in your code behind handler so you can access the databound item easily...
• You can use Databinder.Eval to dynamically populate a Repeater in your ListView using something like this (note 'GetChildCategoryData' is a code behind method):

Hope it helps..

<asp:ListView ID="parentList" runat="server">
   <ItemTemplate>
      <asp:Repeater ID="childData" runat="server" DataSource='<%# GetChildCategoryData(DataBinder.Eval(Container.DataItem, "parentcategoryID")) %>'>.. </asp:Repeater>
   </ItemTemplate>
</asp:ListView>

Answer 3

maybe your answer is to bind a repeater inside the itemTemplate

and the repeater will get the datasource of the <%# Eval("DataDictionary") %>.