如何美元selectedindexchange为DropDownList的p $ pvent整页回发 [英] How to prevent full page postback on selectedindexchange for dropdownlist

问题描述

 ＆LT; ASP：的UpdatePanel =服务器的ClientIDMode =静态ID =TasksUpdatePanel的UpdateMode =条件＆GT;
    ＆LT;＆的ContentTemplate GT;
        ＆LT; ASP：面板ID =pnlDropDown=服务器的ClientIDMode =静态的CssClass =pnlDropDown＆GT;
            ＆LT;！ - 任务名称 - ＆GT;
            ＆LT; ASP：DropDownList的ID =ddlTask​​Name的CssClass =选择选的DataSourceID =dsPopulateTaskName的AutoPostBack =真DataValueField =任务名称=服务器WIDTH =100％FONT-SIZE =11像素AppendDataBoundItems =真OnSelectedIndexChanged =ddlTask​​Name_onSelectIndexChanged＆GT;
                ＆LT; ASP：ListItem的文本=所有VALUE =％＆GT;＆LT; / ASP：ListItem的＆GT;
            ＆LT; / ASP：DropDownList的＆GT;        ＆LT; / ASP：面板＆gt;
        ＆LT; ASP：GridView的ShowHeaderWhenEmpty =false的AlternatingRowStyle-背景色=＃EBE9E9的AutoGenerateColumns =false的OnSorting =yourTasksGV_SortingAllowSorting =真正的ID =yourTasksGV=服务器的ClientIDMode =静态EmptyDataText = 你现在有没有任务分配给你OnRowDataBound =yourTasksGV_RowDataBoundOnRowCreated =yourTasksGV_RowCreated＆GT;
            ＆LT;柱体和GT;
                ＆LT; ASP：的TemplateField HeaderStyle宽度=2％＆GT;
                    ＆LT;＆ItemTemplate中GT;
                        ＆LT; ASP：ImageButton的的ImageUrl =〜/ cies.png=服务器ID =btnShowDepend按需=btnShowDepend_Command的CommandName =TaskDependCommandArgument ='＆LT;％＃的eval（的TestIt）％＆GT; 工具提示=点击查看相关性/＆GT;
                    ＆LT; / ItemTemplate中＆GT;
                ＆LT; / ASP：的TemplateField＆GT;
                ＆LT; ASP：HyperLinkField字段HeaderStyle-WIDTH =16％目标=_自我DataNavigateUrlFields =任务详细信息DataTextField =任务名称DataNavigateUrlFormatString =的HeaderText =任务详细信息SORTEX pression =任务名称 ItemStyle-的CssClass =taskTableColumn/＆GT;
                ＆LT; ASP：BoundField的HeaderStyle-WIDTH =10％的数据字段=工作组的HeaderText =工作组SORTEX pression =工作组ItemStyle-的CssClass =taskTableColumn/＆GT;
                ＆LT; ASP：BoundField的HeaderStyle宽度=7％数据字段=状态的HeaderText =状态SORTEX pression =状态ItemStyle-的CssClass =taskTableColumn/＆GT;
            ＆LT; /专栏＆GT;
        ＆LT; / ASP：GridView的＆GT;
    ＆LT; /＆的ContentTemplate GT;
    ＆LT;％ - ＆LT;＆触发器GT;
        ＆LT; ASP：AsyncPostBackTrigger控件ID =ddlTask​​Name事件名称=onSelectIndexChanged/＆GT;
    ＆LT; /触发器＆GT;  - ％GT;
＆LT; / ASP：的UpdatePanel＆GT;
 

每当执行 ddlTask​​Name_onSelectIndexChanged 函数有一个完整的网页回发，而不仅仅是更新的UpdatePanel

ddlTask​​Name_onSelectIndexChanged 功能：

 保护无效ddlTask​​Name_onSelectIndexChanged（对象发件人，EventArgs的发送）
{
    PullData（的ViewState [sortExp]的ToString（）的ViewState [中将sortOrder]的ToString（）为false。）; //调用一个函数来更新GridView控件
}
 

通过上面的code，页面做一个完整的回发，而不仅仅是部分（只更新GridView的），只要该指数是在改变了 ddlTask​​Name

我可以添加/什么code修改，以确保不执行完全回发，只更新GridView的索引改变。

以为......我是否需要添加它们在两个单独的UpdatePanel？

如果我取消注释触发，我收到以下错误： ID为ddlTask​​Name控制找不到在UpdatePanel的触发器TasksUpdatePanel。

我附上的DropDownList到GridView是这样的：

是不是因为这样的：

 保护无效yourTasksGV_RowCreated（对象发件人，GridViewRowEventArgs E）
{
    如果（e.Row.RowType == DataControlRowType.Header）
    {
        GridView控件hGrid =（GridView的）发件人;
        GridViewRow gvrRow =新GridViewRow（0，0，DataControlRowType.Header，DataControlRowState.Insert）;        TableHeaderCell tcCellTask​​ =新TableHeaderCell（）;
        tcCellTask​​.Controls.Add（ddlTask​​Name）;
        gvrRow.Cells.Add（tcCellTask​​）;        yourTasksGV.Controls [0] .Controls.AddAt（0，gvrRow）;
    }
}
 

解决方案

您code似乎罚款。你尝试注释掉的asp：面板标签？
如果你unccoment触发器，你需要把ASP：GridView的周围的UpdatePanel

<asp:UpdatePanel runat="server" ClientIDMode="Static" ID="TasksUpdatePanel" UpdateMode="Conditional">
    <ContentTemplate>
        <asp:Panel ID="pnlDropDown" runat="server" ClientIDMode="Static" CssClass="pnlDropDown">
            <!-- TASK NAME -->
            <asp:DropDownList ID="ddlTaskName" CssClass="chosen-select" DataSourceID="dsPopulateTaskName" AutoPostBack="true" DataValueField="Task Name" runat="server" Width="100%" Font-Size="11px" AppendDataBoundItems="true" OnSelectedIndexChanged="ddlTaskName_onSelectIndexChanged">
                <asp:ListItem Text="All" Value="%"></asp:ListItem>
            </asp:DropDownList>

        </asp:Panel>
        <asp:GridView ShowHeaderWhenEmpty="false" AlternatingRowStyle-BackColor="#EBE9E9" AutoGenerateColumns="false" OnSorting="yourTasksGV_Sorting" AllowSorting="true" ID="yourTasksGV" runat="server" ClientIDMode="Static" EmptyDataText="You currently have no tasks assigned to you" OnRowDataBound="yourTasksGV_RowDataBound" OnRowCreated="yourTasksGV_RowCreated">
            <Columns>
                <asp:TemplateField HeaderStyle-Width="2%">
                    <ItemTemplate>
                        <asp:ImageButton ImageUrl="~/cies.png" runat="server" ID="btnShowDepend" OnCommand="btnShowDepend_Command" CommandName="TaskDepend" CommandArgument='<%#Eval("TestIt") %>' ToolTip="Click to view Dependencies" />
                    </ItemTemplate>
                </asp:TemplateField>
                <asp:HyperLinkField HeaderStyle-Width="16%" Target="_self" DataNavigateUrlFields="Task Detail" DataTextField="Task Name" DataNavigateUrlFormatString="" HeaderText="Task Detail" SortExpression="Task Name" ItemStyle-CssClass="taskTableColumn" />
                <asp:BoundField HeaderStyle-Width="10%" DataField="Workgroup" HeaderText="Workgroup" SortExpression="Workgroup" ItemStyle-CssClass="taskTableColumn" />
                <asp:BoundField HeaderStyle-Width="7%" DataField="Status" HeaderText="Status" SortExpression="Status" ItemStyle-CssClass="taskTableColumn" />
            </Columns>
        </asp:GridView>
    </ContentTemplate>
    <%--<Triggers>
        <asp:AsyncPostBackTrigger ControlID="ddlTaskName" EventName="onSelectIndexChanged" />
    </Triggers>--%>
</asp:UpdatePanel>

Whenever the ddlTaskName_onSelectIndexChanged function is executed there is a full page postback rather than just updating the UpdatePanel

ddlTaskName_onSelectIndexChanged function:

protected void ddlTaskName_onSelectIndexChanged(object sender, EventArgs e)
{
    PullData(ViewState["sortExp"].ToString(), ViewState["sortOrder"].ToString(), false); //calls a function to update the GridView
}

With the above code, the page does a full postback rather than just partial (only update the GridView) whenever the index is changed in the ddlTaskName

What code can I add/modify to ensure the full postback isn't executed and only update the GridView on index changed.

Thought... Do I need to add them in two separate UpdatePanel?

If I uncomment the triggers, I get the following error: A control with ID 'ddlTaskName' could not be found for the trigger in UpdatePanel 'TasksUpdatePanel'.

I am attaching the dropdownlist to the Gridview like this:

Is it because of this:

protected void yourTasksGV_RowCreated(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.Header)
    {
        GridView hGrid = (GridView)sender;
        GridViewRow gvrRow = new GridViewRow(0, 0, DataControlRowType.Header, DataControlRowState.Insert);

        TableHeaderCell tcCellTask = new TableHeaderCell();
        tcCellTask.Controls.Add(ddlTaskName);
        gvrRow.Cells.Add(tcCellTask);

        yourTasksGV.Controls[0].Controls.AddAt(0, gvrRow);
    }
}

解决方案

your code seems fine. did you try to comment out asp:Panel tab? if you unccoment triggers, you need to put asp:UpdatePanel around gridview

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