Refreshing gridview with new data

Question

I have a combobox and a gridview. whenever an item from the combobox is selected  the gridview should be populated with related records. My question is how can we refresh the datagridview with new data and remove the old one. Right now when i click on combobox item A  the gridview displays item A records. Then when i select combobox item B the gridview displays Item A and B records. I only want item B records to be displayed

Dipankar Biswas · Answer

Hi... try.. celect change event.. private void search_d() { if (connectiondb.State == ConnectionState.Closed) { connectiondb.Open(); } //Select_sub_or_date_for_result frm = new Select_sub_or_date_for_result(); string all_data_query = Select Main_idSNameMrk_RMrk_Wmark from tbl_result where sub=' + comboBox2.Text.Trim() + ' and Exam_date=' + dateTimePicker2.Text + ' ; com = new OleDbCommand(all_data_query connectiondb); com.CommandType = CommandType.Text; OleDbDataAdapter da = new OleDbDataAdapter(com); DataTable dt = new DataTable(); da.Fill(dt); this.dataGridView1.DataSource = dt; connectiondb.Close(); }