DataTable去除重复的行，绑定到下拉菜单，并点击下列菜单显示不同数据。

DataTable  dt=db.GetDt("select * from 表名");            //获得datatab

DataView dView = new DataView(dt);                           //虚拟视图

DataTable dt2 = dView.ToTable(true, "name","age");//去除重复行

//绑定下拉菜单

DataRow row = dt2.NewRow();
row["age"] = "--请选择年龄--";
row["name"] = -1;
dt2.Rows.InsertAt(row, 0);
this.cmbMenu.DataSource = dt2;
this.cmbMenu.DisplayMember = "age";
this.cmbMenu.ValueMember = "name";
this.cmbMenu.SelectedItem = "-1";

 

private void cmbMenu_SelectionChangeCommitted(object sender, EventArgs e)
        {
            string sValue = this.cmbMenu.SelectedValue.ToString();
            if (sValue != "-1")
            {
                string sText = this.cmbMenu.Text;
                dView.RowFilter = "[工序] like '%" + sText + "%'";
                this.dgMaster.DataSource = dView.ToTable();
            }
            else
            {
                dView.RowFilter = "[工序] like '% %'";
                this.dgMaster.DataSource = dView.ToTable();
            }
        }

dView.ToTable(true, "name","age");
第一个参数，true  去除重复，false 不去除
第二个参数，需要显示的字段。