玩转DataGridView之行的展开与收缩

if (this.dataGridView1.Columns[e.ColumnIndex].Name == "EX" && isEx == "true")  
           {  
               string id = this.dataGridView1.Rows[e.RowIndex].Cells["ID"].Value.ToString();  
               DataTable table = GetDataTable("select * from Department where DparentId=" + id);  
               if (table.Rows.Count > 0)  
               {  
                   //利用Remove  
                   for (int i = 0; i < table.Rows.Count; i++)  
                   {  
                       foreach (DataGridViewRow row in this.dataGridView1.Rows)  
                       {  
                           if (row.Cells["ID"].Value.Equals(table.Rows[i]["ID"]))  
                           {  
                               this.dataGridView1.Rows.Remove(row);  
                           }  
                       }  
                   }  
               }  
               ////将IsEx设置为false，标明该节点已经收缩  
               this.dataGridView1.Rows[e.RowIndex].Cells["IsEx"].Value = "false";  
               this.dataGridView1.Rows[e.RowIndex].Cells["EX"].Value = "+";  
           } 

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