Find a control by id from Dynamically added Template field in GridView

asp.netgridview

Hi i added template field dynamically to gridview by implementing ITemplate interface.
The template field contains some controls like label and textboxes. how do i get these controls in row databound event.

I am not able to get when i do gridviewrow.findcontrol("id") as i do normally when we add templatefield from aspx page.

The way i added template field is like this

public class CustomGridViewColumn : ITemplate
{
ListItemType _liType;
string _columnName;

        public CustomGridViewColumn(ListItemType type, string column)
        {
            _liType = type;
            _columnName = column;

        }
        void ITemplate.InstantiateIn(System.Web.UI.Control container)
        {
            switch (_liType)
            {
                case ListItemType.Header:
                    Label lblHeader = new Label();
                    lblHeader.Text = _columnName;
                    container.Controls.Add(lblHeader);
                    break;
                case ListItemType.Item:
                    Label lblItem = new Label();
                    lblItem.DataBinding += new EventHandler(lbl_DataBinding);
                    lblItem.ID = "lbl" + _columnName;
                    lblItem.ClientIDMode = ClientIDMode.Predictable;
                    container.Controls.Add(lblItem);

                    DropDownList ddl = new DropDownList();

                    ddl.DataBinding += new EventHandler(ddl_DataBinding);
                    ddl.ID = "ddl" + _columnName;
                    ddl.Visible = false;
                    container.Controls.Add(ddl);
                    break;


            }
        }

}

Now i want access the label and dropdown which i have added using this code.
when i do gridviewrow.findcontrol("id") i am not getting them.
Can any one please help me.

I am geeting when i go through all the rows and try to find but
i have a check box in a row when i select it all labels should diappear and ddls dhould appear
for this i am using the follwoing code.

protected void chkEdit_CheckedChanged(object sender, EventArgs e)
{
CheckBox chkEditTest = (CheckBox)sender;
GridViewRow grow = (GridViewRow)chkEditTest.NamingContainer;
DropDownList ddl = (DropDownList)grow.FindControl("ddl");
Label lbl= (Label)grow.FindControl("lbl");
}

when i do this i am not able to get the controls.
it seems like controls are disapppearing on postback..

Best Answer

This is what I came up with and I can able to get the control reference in the code behind. 

    public class CustomGridViewColumn : ITemplate
    {
    ListItemType _liType; string _columnName;

    public CustomGridViewColumn(ListItemType type, string column)
    {
        _liType = type;
        _columnName = column;

    }

    void ITemplate.InstantiateIn(Control container)
    {
        switch (_liType)
        {
            case ListItemType.Header:
                Label lblHeader = new Label();
                lblHeader.Text = _columnName;
                container.Controls.Add(lblHeader);
                break;
            case ListItemType.Item:
                Label lblItem = new Label();
                lblItem.DataBinding += new EventHandler(lblItem_DataBinding);
                lblItem.ID = "lbl" + _columnName;
                lblItem.ClientIDMode = ClientIDMode.Predictable;
                container.Controls.Add(lblItem);

                DropDownList ddl = new DropDownList();

                ddl.DataBinding += new EventHandler(ddl_DataBinding);
                ddl.ID = "ddl" + _columnName;
                ddl.Visible = false;
                ddl.DataSource = new string[] { "Hello", "World" };
                container.Controls.Add(ddl);
                break;


        }
    }

    void ddl_DataBinding(object sender, EventArgs e)
    {

    }

    void lblItem_DataBinding(object sender, EventArgs e)
    {

    }

}

 protected void Page_Load(object sender, EventArgs e)
 {

    DataTable dt = new DataTable();
    dt.Columns.Add("Name");
    DataRow oItem = dt.NewRow();
    oItem[0] = "Deepu";
    dt.Rows.Add(oItem);
    oItem = dt.NewRow();
    oItem[0] = "MI";
    dt.Rows.Add(oItem);
    GridView gv = new GridView();
    gv.ID = "myGridView";
    gv.AutoGenerateColumns = false;
    BoundField nameColumn = new BoundField();
    nameColumn.DataField = "Name";
    nameColumn.HeaderText = "Name";
    gv.Columns.Add(nameColumn);

    TemplateField TmpCol = new TemplateField();
    TmpCol.HeaderText = "Template Column";
    gv.Columns.Add(TmpCol);
    TmpCol.ItemTemplate = new CustomGridViewColumn(ListItemType.Item, "TEST");
    gv.DataSource = dt;
    gv.DataBind();
    Form.Controls.Add(gv);


}
protected void Button1_Click(object sender, EventArgs e)
{
    GridView gv = Form.FindControl("myGridView") as GridView;
    foreach (GridViewRow item in gv.Rows)
    {
        var ddl = item.FindControl("ddlTest") as DropDownList;
        if (ddl != null)
        {
            ddl.Visible = true;
        }

        var lbl = item.FindControl("lbl") as Label;
        if (lbl != null)
        {
            lbl.Text = "hello";
        }
    }
}

<form id="form1" runat="server">


<asp:Button ID="Button1" runat="server" onclick="Button1_Click" Text="Button" />


</form>

Thanks

Deepu

Related Topic