Adding new rows dynamically in a grid view or datatable in asp.net?

Question

I am binding the grid view using data table.

My task is to add new rows to my grid view dynamically when the user clicks \"ADD\" button in grid view it should genera

Answer 1

you could try this solution

inside code behind

Here’s the code block below:

private void SetInitialRow()
{
    DataTable dt = new DataTable();
    DataRow dr = null;
    dt.Columns.Add(new DataColumn("RowNumber", typeof(string)));
    dt.Columns.Add(new DataColumn("Column1", typeof(string)));
    dt.Columns.Add(new DataColumn("Column2", typeof(string)));
    dt.Columns.Add(new DataColumn("Column3", typeof(string)));
    dr = dt.NewRow();
    dr["RowNumber"] = 1;
    dr["Column1"] = string.Empty;
    dr["Column2"] = string.Empty;
    dr["Column3"] = string.Empty;
    dt.Rows.Add(dr);
    //dr = dt.NewRow();

    //Store the DataTable in ViewState
    ViewState["CurrentTable"] = dt;

    Gridview1.DataSource = dt;
    Gridview1.DataBind();
}

in page load you have to call this method

  protected void Page_Load(object sender, EventArgs e)
  {
    if (!Page.IsPostBack)
    {
        SetInitialRow(); 
    }
 }

this is the method for generating the rows when clicking the Button. Here are the code blocks below:

private void AddNewRowToGrid()
{
    int rowIndex =0;

    if (ViewState["CurrentTable"] != null)
    {
        DataTable dtCurrentTable = (DataTable)ViewState["CurrentTable"];
        DataRow drCurrentRow = null;
        if (dtCurrentTable.Rows.Count > 0)
        {
            for (int i = 1; i <= dtCurrentTable.Rows.Count; i++)
            {
                //extract the TextBox values
                TextBox box1 = (TextBox)Gridview1.Rows[rowIndex].Cells[1].FindControl("TextBox1");
                TextBox box2 = (TextBox)Gridview1.Rows[rowIndex].Cells[2].FindControl("TextBox2");
                TextBox box3 = (TextBox)Gridview1.Rows[rowIndex].Cells[3].FindControl("TextBox3");

                drCurrentRow = dtCurrentTable.NewRow();
                drCurrentRow["RowNumber"] = i + 1;
                drCurrentRow["Column1"] = box1.Text;
                drCurrentRow["Column2"] = box2.Text;
                drCurrentRow["Column3"] = box3.Text;

                rowIndex++;
            }
            //add new row to DataTable
            dtCurrentTable.Rows.Add(drCurrentRow);
            //Store the current data to ViewState
            ViewState["CurrentTable"] = dtCurrentTable;

            //Rebind the Grid with the current data
            Gridview1.DataSource = dtCurrentTable;
            Gridview1.DataBind();
        }
    }
    else
    {
        Response.Write("ViewState is null");
    }

    //Set Previous Data on Postbacks
    SetPreviousData();
}

this is setpreviousdata method...

 private void SetPreviousData()
{
    int rowIndex = 0;
    if (ViewState["CurrentTable"] != null)
    {
        DataTable dt = (DataTable)ViewState["CurrentTable"];
        if (dt.Rows.Count > 0)
        {
            for (int i = 1; i < dt.Rows.Count; i++)
            {
                TextBox box1 = (TextBox)Gridview1.Rows[rowIndex].Cells[1].FindControl("TextBox1");
                TextBox box2 = (TextBox)Gridview1.Rows[rowIndex].Cells[2].FindControl("TextBox2");
                TextBox box3 = (TextBox)Gridview1.Rows[rowIndex].Cells[3].FindControl("TextBox3");

                box1.Text = dt.Rows[i]["Column1"].ToString();
                box2.Text = dt.Rows[i]["Column2"].ToString();
                box3.Text = dt.Rows[i]["Column3"].ToString();

                rowIndex++;

            }
        }
    }
}

button click event for adding new row

protected void ButtonAdd_Click(object sender, EventArgs e)
{
    AddNewRowToGrid();
}

and pls take a look below image how it will generate new rows....

I hope it will helps you.....