title: GridView dynamic Controls are emptied upon clicking edit/update/delete buttons. Asp.net
body: <p>I have a gridview that is being dynamically populated using a custom template, but the command fields are static. Upon clicking the command fields, the controls are understandably lost. This problem doesn't affect me during edit, because once the gridview is rebound, it would know it is in edit mode and create the dynamic edit template fields. But once I make changes to these fields, which are textboxes, I would need to click on the Update command field to instantiate my update method. Upon clicking, the controls are immediately lost, so in my update method I cannot find the controls to which changes have been made. Any ideas how to solve this? I will post code if needed.</p>
  
  <p>The Grid View Template. Here is where the databindings happen upon dynamic generation. Getting the data from the table and reproducing it on the grid view works fine.</p>
  
  <pre><code>public class GridViewTemplate : System.Web.UI.Control, System.Web.UI.ITemplate
  {
      // static attributes here
  
      // constructor
      public GridViewTemplate(DataControlRowType type, string columnName, string categoryID, string itemControl, string editControl, string footerControl, string dataBinds)
      {
          DataRowType = type; // Header, DataRow,
          st_columnName = columnName; // Header name
          st_categoryId = categoryID;
          if (itemControl != null)
              st_itemControl = itemControl.ToUpper(); // Control type for Item Template
          if (editControl != null)
              st_editControl = editControl.ToUpper(); // Control type for Edit Template
          if (footerControl != null)
              st_footerControl = footerControl.ToUpper(); // Control type for Footer Template
          if (dataBinds != null)
              st_dataBinds = dataBinds;
      }
  
      public void InstantiateIn(Control container)
      {
          switch (DataRowType)
          {
              case DataControlRowType.Header:
                  {
                      // Build the header for this column
                      Label lb_header = new Label();
                      lb_header.Text = "&lt;b&gt;" + st_columnName + "&lt;/b&gt;";
                      lb_header.ID = st_categoryId;
                      container.Controls.Add(lb_header);
                  }
                  break;
              case DataControlRowType.DataRow:
                  {
                      if (Regex.IsMatch(st_categoryId,"^(xxI_)")) // item mode
                      {
                          if (st_itemControl.Equals(LABEL))
                          {
                              // For Label
                          }
                          else if (st_itemControl.Equals(TEXTBOX))
                          {
                              TextBox dcrt_textbox = new TextBox();
                              dcrt_textbox.ID = st_categoryId;
                              dcrt_textbox.Visible = true;
                              dcrt_textbox.Enabled = false;
                              dcrt_textbox.DataBinding += new EventHandler(this.TextBox_DataBinding);
                              container.Controls.Add(dcrt_textbox);
                          }
                          else if (st_itemControl.Equals(CHECKBOX))
                          {
                              // For checkbox
                          }
  
                      }
                      else if (Regex.IsMatch(st_categoryId, "^(xxE_)")) // edit mode
                      {
                          if (st_editControl.Equals(LABEL))
                          {
                              // For label
                          }
                          else if (st_editControl.Equals(TEXTBOX))
                          {
                              TextBox dcrt_textbox = new TextBox();
                              dcrt_textbox.ID = st_categoryId;
                              dcrt_textbox.Visible = true;
                              dcrt_textbox.EnableViewState = true;
                              dcrt_textbox.AutoPostBack = false;
                              dcrt_textbox.ViewStateMode = ViewStateMode.Enabled;
                              dcrt_textbox.DataBinding += new EventHandler(this.TextBox_DataBinding);
  
                              container.Controls.Add(dcrt_textbox);
                          }
                          else if (st_editControl.Equals(CHECKBOX))
                          {
                              // For checkbox
                          }
                      }
                  }
                  break;
              case DataControlRowType.EmptyDataRow:
                  // To be implemented when necessary
                  break;
              case DataControlRowType.Pager:
                  // To be implemented when necessary
                  break;
              case DataControlRowType.Separator:
                  // To be implemented when necessary
                  break;
              default:
                  break;
          }
      }
  
      public void TextBox_DataBinding(Object sender, EventArgs e)
      {
          TextBox tb_databound = (TextBox)sender;
          GridViewRow row = (GridViewRow)tb_databound.NamingContainer;
          string RawValue = DataBinder.Eval(row.DataItem, st_columnName).ToString();
          tb_databound.Text = RawValue;
      }
  
      public void Label_DataBinding(Object sender, EventArgs e)
      {
          Label lb_databound = (Label)sender;
          GridViewRow row = (GridViewRow)lb_databound.NamingContainer;
          string RawValue = DataBinder.Eval(row.DataItem, st_columnName).ToString();
          lb_databound.Text = RawValue;
      }
  
      public void CheckBox_DataBinding(Object sender, EventArgs e)
      {
          CheckBox cb_databound = (CheckBox)sender; // get the control that raised this event
          GridViewRow row = (GridViewRow)cb_databound.NamingContainer; // get the containing row
          string RawValue = DataBinder.Eval(row.DataItem, st_columnName).ToString();
  
          if (RawValue.ToUpper().Equals("TRUE"))
          {
              cb_databound.Checked = true;
          }
          else
          {
              cb_databound.Checked = false;
          }
      }
  }
  }
  </code></pre>
  
  <p>The onEdit and onUpdate methods.</p>
  
  <pre><code>protected void onRowEditing(object sender, GridViewEditEventArgs e)
      {
          gv.EditIndex = e.NewEditIndex;
  
          tableBind(ViewState["table"]); // View state contains the table, which is then passed to a bind method that binds the gridview.
  
      }
  protected void onRowUpdating(object sender, GridViewUpdateEventArgs e)
      {
          GridViewRow row = gv_rebateTable.Rows[e.RowIndex];
  
          // at this point, xxE_tier (a textbox in edit mode) was destroyed
          TextBox tb = row.FindControl("xxE_tier") as TextBox;
  
      }
  </code></pre>
  
  <p>Gridview:</p>
  
  <pre><code>&lt;asp:GridView ID="gv" EnableViewState="true" ViewStateMode="Enabled" OnRowEditing="onRowEditing" OnRowCancelingEdit="onRowCancelingEdit" OnRowUpdating="onRowUpdating" OnRowDeleting="onRowDeleting" EnableModelValidation="true" ShowFooter="true" OnRowCommand="onRowCommand" AutoGenerateColumns="False" runat="server"&gt;
      &lt;Columns&gt;  
          &lt;asp:ButtonField Text="Analysis" ButtonType="Button" HeaderText="" ShowHeader="True"  /&gt; 
          &lt;asp:CommandField EditText="Edit" ButtonType="Button" HeaderText="" ShowEditButton="True" ShowHeader="True" ValidationGroup="Edit_Group"/&gt;
          &lt;asp:CommandField EditText="Delete" ButtonType="Button" HeaderText="" ShowDeleteButton="True" ShowHeader="True" /&gt;    
      &lt;/Columns&gt;
  &lt;/asp:GridView&gt;
  </code></pre>