如何在Gridview asp.net上添加文本框值

Question

我有一个带有模板列的gridview，我想将每个定义列的文本框值发送到gridview。我尝试过打击代码，但列显示为双重。我使用telerik控件进行gridview

 <telerik:RadGrid ID="RadGrid1" runat="server">
    <MasterTableView>

        <Columns>
            <telerik:GridBoundColumn DataField="BrandName" 
  HeaderText="Brand Name" UniqueName="BrandName"

                            <HeaderStyle Width="170px" />

                        </telerik:GridBoundColumn>
        </Columns>
    </MasterTableView>
</telerik:RadGrid>

后端代码

    DataTable dt = new DataTable();
    protected void Page_Load(object sender, EventArgs e)
    {

        if (!Page.IsPostBack)
        {
            dt = new DataTable();
            MakeDataTable();
        }
        else
        {
            dt = (DataTable)ViewState["DataTable"];
        }
        ViewState["DataTable"] = dt;


    }
    private void MakeDataTable()
    {
        dt.Columns.Add("BrandName");

    }

    private void AddToDataTable()
    {
        DataRow dr = dt.NewRow();
        dr["BrandName"] = brandname.Text;

        dt.Rows.Add(dr);
    }



    private void BindGrid()
    {

        RadGrid1.DataSource = dt;
        RadGrid1.DataBind();
    }

    protected void Button1_Click(object sender, EventArgs e)
    {
        AddToDataTable();
        BindGrid();
    }

上面的代码在点击时显示2列