protected void cmb1_OnSelectedIndexChanged(object sender,EventArgs e)
{
long value = Convert.Int64(cmb1.SelectedValue);
FillCombo2(value);
}
void FillCombo2(long Combo1Value)
{
cmb2.Items.Clear();
cmb2.dataSource = dt1;
cmb2.DisplayMember ="Name";
cmb2.ValueMember ="Id";
cmb2.DataBind();
}
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