C# Tricks

Datable

Read a Column

Select the row and then ask for the field.

• DataTable requestedTags;
• requestedTags.Rows[0]["status"]

GridView

Add a field

• To add a field beyond the result of your query use <asp:TemplateField>

               <asp:TemplateField HeaderText="New On Board Week">

                        <ItemTemplate>

                            <asp:DropDownList ID="ddlChange" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ddlChange_SelectedIndexChanged">

                                <asp:ListItem>--Change in:--</asp:ListItem>

                                <asp:ListItem>User</asp:ListItem>

                                <asp:ListItem>Plates</asp:ListItem>

                                <asp:ListItem>Car</asp:ListItem>

                            </asp:DropDownList>

                        </ItemTemplate>

                    </asp:TemplateField>

Add a button and define its action

• Add the button in the gridView
• Define the CommmandName
• <asp:ButtonField ButtonType="Button" Text="Select" CommandName="Select"  />
• Define in the gridView the property OnRowCommand="grdData_RowCommand"
• In the code part create the method that you define in the OnRowCommand 
• To filter the commands inside the method

 if (e.CommandName == "Select")

            {

           }

Know row index

• Inside the method of the element inside the GridView
• Cast the sender to your element type
• From that cast element call the Parent two times to get the GridViewRow
• Now call from the GridViewRow the property RowIndex

protected void ddlActivity_SelectedIndexChanged(object sender, EventArgs e)

    {

        DropDownList ddlCurrentDropDownList = (DropDownList)sender;

        GridViewRow grdrDropDownRow = ((GridViewRow)ddlCurrentDropDownList.Parent.Parent);

        if (String.Compare(ddlCurrentDropDownList.SelectedItem.Value, "-1") != 0)

        {

            DropDownList ddlSubactivity = (DropDownList)gvCreateProject.Rows[grdrDropDownRow.RowIndex].Cells[2].FindControl("ddlSubactivity");

            ddlSubactivity.Enabled = true;

            FillSubactivityDdl(ddlSubactivity, Convert.ToInt32(ddlCurrentDropDownList.SelectedValue));

        }

    }

Add a scraoll

Put the gridview inside a div

<div style="overflow:scroll; height: 100%; width: 100%">

  <asp:GridView ......></asp:GridView>

</div>