Gridview 编辑模版下的Dropdownlist绑定数据库问题

Question

前台：
<asp:TemplateField HeaderText="岗位工资"  >
         <EditItemTemplate>
         <asp:DropDownList ID="gwgz" runat="server" Height="20px" Width="128px"    >  </asp:DropDownList>
         </EditItemTemplate>
                                    
 <ItemTemplate  >
   <asp:Label ID="岗位工资" runat="server" Text='<%# Bind("岗位工资级别")%> '></asp:Label>
  </ItemTemplate> </asp:TemplateField>
                 要达到效果：数据库：

Answer 1

//下拉列表框赋值 
DropDownList S_code = (DropDownList)e.Row.Cells[1].FindControl("S_code"); 
S_code.DataSource = ds; 
S_code.DataTextField = "code"; 
S_code.DataValueField = "code"; S_code.DataBind(); 
//插入的这一句应该放在绑定之后，不然会被绑定数据给替换掉
S_code.Items.Insert(0, "请选择");(DropDownList)e.Row.Cells[1].FindControl("S_code"); 这段代码就可以了  寻找Gridview中的这个控件 然后来绑定

Answer 2

GridView1_RowEditing状态下会出错  

Answer 3

“System.Web.UI.WebControls.GridViewEditEventArgs”不包含“Row”的定义，

Answer 4

 sqlcon = db.GetCon();
         OleDbDataAdapter da = new OleDbDataAdapter("select * from 岗位工资 ", sqlcon);
         DataSet ds = new DataSet();
         da.Fill(ds);         //下拉列表框赋值 
         DropDownList S_code = (DropDownList)e.Row.Cells[4].FindControl("gwgz");
         S_code.DataSource = ds;
         S_code.DataTextField = "级别";
         S_code.DataValueField = "岗位工资";
         S_code.DataBind();System.NullReferenceException: 未将对象引用设置到对象的实例。

Answer 5

protected void gv_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowIndex != -1) {
if (e.Row.RowState == DataControlRowState.Edit || Convert.ToInt32(e.Row.RowState & DataControlRowState.Edit) != 0) {
DropDownList ddl = e.Row.FindControl("ddl") as DropDownList;
ddl.SelectedValue = ((HiddenField)e.Row.FindControl("Hf")).Value;}
}}
protected void gv_RowEditing(object sender, GridViewEditEventArgs e)
{
gv.EditIndex = e.NewEditIndex;
BindData();
}
protected void gv_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
gv.EditIndex = e.RowIndex;
int id = int.Parse(gv.DataKeys(e.RowIndex).Value.ToString());
string str = ((DropDownList)gv.Rows(e.RowIndex).FindControl("ddl")).SelectedValue.Trim();
}

Answer 6

protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
    {
        DropDownList ddl = GridView1.Rows[e.NewEditIndex].FindControl("gwgz") as DropDownList;
        
        ddl.Items.Insert(0, new ListItem("请选择", "0"));
    }

Answer 7

ddl.Items.Insert(0, new ListItem("请选择", "0"));
异常详细信息: System.NullReferenceException: 未将对象引用设置到对象的实例。

Answer 8

非编辑状态下  RowDataBound中能找到控件？

Answer 9

protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
    {
        DropDownList ddl = GridView1.Rows[e.NewEditIndex].FindControl("DropDownList1") as DropDownList;
        //找到编辑行中的dropDownList对象
    }
    protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            DropDownList ddl = e.Row.FindControl("DropDownList1") as DropDownList;
            //绑定数据
            ddl.Items.Add(new ListItem("请选择", "0"));
        }
        
    }

Answer 10

把DropDownList1 改成 你的DropDownList控件的ID值 gwgz

Answer 11

ddl.Items.Add(new ListItem("请选择", "0"));未将对象引用设置到对象的实例。

Answer 12

 protected void gv销售_销售计划明细_RowDataBound(object sender, GridViewRowEventArgs e)
        {
            if (e.Row.RowType == DataControlRowType.DataRow)
            {
               DropDownList ddl销售策略 = e.Row.FindControl("ddl销售策略") as DropDownList;
                if (ddl销售策略 != null)
                {
                    ddl销售策略.Items.Clear();
                    ddl销售策略.DataSource = BLL.BaseSetting.基础_销售策略.GetDataTable(new Entity.BaseSetting.基础_销售策略查询());
                    ddl销售策略.DataTextField = "销售策略名称";
                    ddl销售策略.DataValueField = "销售策略ID";
                    ddl销售策略.DataBind();
                    ddl销售策略.Items.Insert(0, new ListItem("--请选择--", ""));                    if (DataBinder.Eval(e.Row.DataItem, "销售策略ID") != null)
                    {
                        ddl销售策略.SelectedValue = DataBinder.Eval(e.Row.DataItem, "销售策略ID").ToString();
                    }
                    else
                    {
                        ddl销售策略.SelectedIndex = 0;
                    }
                }
                 
            }
        }