How to retain form fields values when page reload?

Hi,

I have a form with few fields and datagrid.If I say something about datagrid there is a button "Add".When you click this it will open another
form with some values where I can select one of the value and click ok.Then selected value needs to come to datagrid.I have implement that using below method.

set {
DataGridViewRow row = (DataGridViewRow)dataGridView1.Rows[0].Clone();
row.Cells[0].Value = value;
row.Cells[1].Value = "Name";
dataGridView1.Rows.Add(row);
}

So it updates the datagrid.But after it updates I need to use

dataGridView1.Update();
dataGridView1.Refresh();

for show the result in datagrid.This makes my form reload and lost previously entered data.

1.How can I retain previously enter values when form reload?
2.Is there any way to update datagrid without reload?

Thanks

Instead of directly storing the values in gridview cell you can create a data table and store your value there and bind that data table to your grid.

For asp code check this

DataTable dt = null;

protected void Page_Load(object sender, EventArgs e)

{

dt = new DataTable();

dt.Columns.Add(new DataColumn("value"));

dt.Columns.Add(new DataColumn("Name"));

dtTemp = dt;

}

protected void Button1_Click(object sender, EventArgs e)

{

dt = dtTemp;

DataRow dr = dt.NewRow();

dr["value"] = TextBox1.Text;

dr["Name"] = "name";

dt.Rows.Add(dr);

GridView1.DataSource = dt;

GridView1.DataBind();

dtTemp = dt;

}

private DataTable dtTemp

{

get { return (DataTable)ViewState["Parameter:dtTemp"]; }

set { ViewState["Parameter:dtTemp"] = value; }

}