Dont want textbox to enter null value in datatable

Question

I have a data table which already has some values, plus it is getting values from a textbox below.

Now my problem is when i dont enter a value in the textbox it still enters in the data table. I dont want it to do that..

The code can run on any machine... any suggestions????

Thanks

public partial class WebForm6 : System.Web.UI.Page
{
    DataTable dt;
    protected void Page_Load(object sender, EventArgs e)
    {


        // Initialize a DataTable

        if (!Page.IsPostBack)
        {
            dt = new DataTable();
            // Initialize DataColumn

            DataColumn myDataColumn = new DataColumn();



            //// initialize a new instance of DataColumn to add another column with different properties.

            //myDataColumn = new DataColumn();

            myDataColumn.ColumnName = "firstName";
            // set DataType property of the column as String

            myDataColumn.DataType = System.Type.GetType("System.String");

            // Add and Create a Second DataColumn

            dt.Columns.Add(myDataColumn);


            // create a new row using NewRow() function of DataTable.

            // dataRow object will inherit the schema of myDataTable to create a new row

            DataRow dataRow = dt.NewRow();

            dataRow["firstName"] = "John";

            // add new data row to the data table.

            dt.Rows.Add(dataRow);

            // similarly adds the second row to the DataTable

            dataRow = dt.NewRow();

            dataRow["firstName"] = "Will";
            dt.Rows.Add(dataRow);
            Session["data"] = dt;

            GridView1.DataSource = dt;
            GridView1.DataBind();

        }
    }

 protected void btnSubmit_Click(object sender, EventArgs e)
    {

  if (Session["Data"] == null)
        {
            dt.Columns.Add("firstName");
            BindtoGridViewFromTextBoxes(dt);
            ClearControls();
        }
    else
    {
        dt = (DataTable)Session["Data"];
        BindtoGridViewFromTextBoxes(dt);
        ClearControls();
    }
    } private void ClearControls()
  {
  txtName.Text = String.Empty;

   }

 private void BindtoGridViewFromTextBoxes(DataTable dt)
     {
        DataRow dr;
        dr = dt.NewRow();

        dr["firstName"] = txtName.Text.ToString();
        dt.Rows.Add(dr);
        Session["Data"] = dt;

        GridView1.DataSource = dt;
        GridView1.DataBind();
    }

and on .aspx page

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False">

<asp:TemplateField>
    <EditItemTemplate>
        <asp:CheckBox ID="CheckBox1" runat="server" />
    </EditItemTemplate>
    <ItemTemplate>
        <asp:CheckBox ID="CheckBox1" runat="server" />
    </ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="First Name">
    <EditItemTemplate>
        <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("firstName") %>'></asp:TextBox>
    </EditItemTemplate>
    <ItemTemplate>
        <asp:Label ID="Label1" runat="server" Text='<%# Bind("firstName") %>'></asp:Label>
    </ItemTemplate>
</asp:TemplateField>

any help....??

Answer 1

Change your method to be this:

private void BindtoGridViewFromTextBoxes(DataTable dt)
{
    if (!String.IsNullOrEmpty(txtname.Text))
    {
        DataRow dr = dt.NewRow();
        dr["firstName"] = txtName.Text;
        dt.Rows.Add(dr);
        Session["Data"] = dt;
    }
    GridView1.DataSource = dt;
    GridView1.DataBind(); 
}