我创建了名为CRE.ascx的用户控件，此控件有3个下拉列表。 第一个下拉列表在pageload.Second和third上基于SelectedIndexChanged绑定数据。
<table cellspacing="0" cellspading="0" style="width:550px;height:30px;">
<tr>
<td style="width:30%;">
<asp:DropDownList ID="ddlCRE" runat="server" Height="20px" Width="145px" OnSelectedIndexChanged="ddlCRE_SelectedIndexChanged" AutoPostBack="true">
</asp:DropDownList>
</td>
<td style="width:30%;">
<asp:DropDownList ID="ddlDataPoints" runat="server" Height="20px" Width="145px" OnSelectedIndexChanged="ddlDataPoints_SelectedIndexChanged" AutoPostBack="true">
</asp:DropDownList>
</td>
<td style="width:30%;">
<asp:DropDownList ID="ddlErrorCode" runat="server" Height="20px" Width="145px" OnSelectedIndexChanged="ddlErrorCode_SelectedIndexChanged" AutoPostBack="true">
</asp:DropDownList>
</td>
<td style="width:10%;">
<asp:TextBox ID="tbxErrorScore" runat="server" style="height:17px;border:0px;font-family:'Segoe UI';font-size:13px;font-weight:500;color:white;background-color:#333333;
width:65px;" ReadOnly="true"> </asp:TextBox>
</td>
</tr>
</table>
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
//Get Ticket Type Values
dbtickettype = helpdsktcktusrHandler.GetTicketType("DPT0001");
ddlCRE.DataSource = dbtickettype;
ddlCRE.DataValueField = "Type_ID";
ddlCRE.DataTextField = "Type_Name";
ddlCRE.DataBind();
ddlCRE.Items.Insert(0, new ListItem("Select Type", "SLCT0000"));
}
else
{
}
}
protected void ddlCRE_SelectedIndexChanged(object sender, EventArgs e)
{
string selectedTypeID = ddlCRE.SelectedValue.ToString();
try
{
if (selectedTypeID == "SLCT0000")
{
ddlDataPoints.Items.Clear();
ddlErrorCode.Items.Clear();
tbxErrorScore.Text = string.Empty;
}
else
{
//Get Category Details
dbticketCategory = helpdsktcktusrHandler.GetTicketCategoryDetails(selectedTypeID);
//Binding Ticket Type values to Listbox
ddlDataPoints.DataSource = dbticketCategory;
ddlDataPoints.DataValueField = "Category_ID";
ddlDataPoints.DataTextField = "Category_Name";
ddlDataPoints.DataBind();
ddlDataPoints.Items.Insert(0, new ListItem("Select Category", "SLCT0000"));
//Clear Items
ddlErrorCode.Items.Clear();
tbxErrorScore.Text = string.Empty;
}
}
catch (Exception ex)
{
}
}
protected void ddlDataPoints_SelectedIndexChanged(object sender, EventArgs e)
{
string selectedCatID = ddlDataPoints.SelectedValue.ToString();
try
{
if (selectedCatID == "SLCT0000")
{
ddlErrorCode.Items.Clear();
tbxErrorScore.Text = string.Empty;
}
else
{
//Get Category Details
dbticketSubCategory = helpdsktcktusrHandler.GetTicketSubCategoryDetails(selectedCatID);
//Binding Ticket Type values to Listbox
ddlErrorCode.DataSource = dbticketSubCategory;
ddlErrorCode.DataValueField = "Sub_Category_ID";
ddlErrorCode.DataTextField = "Sub_Category_Name";
ddlErrorCode.DataBind();
ddlErrorCode.Items.Insert(0, new ListItem("Select Subcategory", "SLCT0000"));
//Clear Items
tbxErrorScore.Text = string.Empty;
}
}
catch (Exception ex)
{
}
}
protected void ddlErrorCode_SelectedIndexChanged(object sender, EventArgs e)
{
string selectedSubcatID = ddlErrorCode.SelectedValue.ToString();
try
{
if (selectedSubcatID == "SLCT0000")
{
tbxErrorScore.Text = string.Empty;
}
else
{
//Get Category Details
dbticketIssues = helpdsktcktusrHandler.GetTicketIssueDetails(selectedSubcatID);
////Binding Ticket Type values to Listbox
//ddlstIssue.DataSource = dbticketIssues;
//ddlstIssue.DataValueField = "IssueID";
//ddlstIssue.DataTextField = "Issue_Name";
//ddlstIssue.DataBind();
tbxErrorScore.Text = dbticketIssues.Rows[0][1].ToString();
}
}
catch (Exception ex)
{
}
}
然后注册指令和添加到页面的用户控件的实例。 在这个主页面中，我添加了一个Gridview，用户控件UC1和两个按钮 包含在ItemTemplate中。
<%@ Register src="~/CRE.ascx" TagName="InsertNewCRE" TagPrefix="uc1" %>
<asp:UpdatePanel ID="MainUpdatePanel" runat="server">
<ContentTemplate>
<div id="dvsubCRE" class="dvsubCRE" runat="server">
<!-----[[[ GRIDVIEW ADDING CRE ]]]----->
<div id="dvAddingErrorInfo" class="dvAddingErrorInfo">
<!-- LOAD CRE DROPDOWN INFO GRID -->
<asp:GridView ID="gvCREInfo" runat="server" CssClass="gvErrorInfo" AlternatingRowStyle-CssClass="" ShowFooter="false" ShowHeader="false"
EnableViewState="True" GridLines="None" EmptyDataText="No records found" AutoGenerateColumns="true" CaptionAlign="Left" CellPadding="0"
ShowHeaderWhenEmpty="True" OnRowCreated="gvCREInfo_RowCreated" OnRowCommand="gvCREInfo_RowCommand" >
<Columns>
<asp:BoundField DataField="RowNumber" />
<asp:TemplateField ItemStyle-Width="25%" ItemStyle-Height="20px">
<ItemTemplate>
<uc1:InsertNewCRE id="UC1InserCRE" runat="server" EnableViewState="true" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField ItemStyle-Width="5%">
<ItemTemplate>
<asp:ImageButton ID="imgbtnAddCRE" runat="server" Width="20px" Height="20px" value="" ImageUrl="~/Images/Tracker/add.png"
CommandName="ButtonAddCRERow" CommandArgument="<%# ((GridViewRow) Container).RowIndex %>" />
<asp:ImageButton ID="imgbtnReoveCRE" runat="server" Width="20px" Height="20px" value="" Visible="false" ImageUrl="~/Images/Tracker/delete.png" CommandName="ButtonRemoveCRERow" CommandArgument="<%# ((GridViewRow) Container).RowIndex %>" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<!-- LOAD CRE DROPDOWN INFO GRID CLOSE -->
</div>
<!-----[[[ GRIDVIEW ADDING CRE CLOSE ]]]----->
</div>
</ContentTemplate>
</asp:UpdatePanel>
当主页加载时，用户控制UC1加载到gridview中并从CRE.ascx页面中提取数据。我将页面加载时的虚拟数据绑定到gridview.Add新行以及RowCommand中提到的用户控件。
protected void Page_Load(object sender, EventArgs e)
{
try
{
if (!IsPostBack)
{
DataTable dt = new DataTable();
DataRow dr = null;
dt.Columns.Add(new DataColumn("RowNumber", typeof(string)));
dr = dt.NewRow();
dr["RowNumber"] = 1;
dt.Rows.Add(dr);
ViewState["CurrentTable"] = dt;
gvCREInfo.DataSource = dt;
gvCREInfo.DataBind();
}
else
{
}
}
catch (Exception ex)
{
}
}
protected void gvCREInfo_RowCommand(object sender, GridViewCommandEventArgs e)
{
#region ADD NEW CRE ROW
if (e.CommandName == "ButtonAddCRERow")
{
int index = Convert.ToInt32(e.CommandArgument);
GridViewRow row = gvCREInfo.Rows[index];
int count = gvCREInfo.Rows.Count;
DataRow drCurrentRow = null;
UserControl UC1 = (UserControl)(row.Cells[0].FindControl("UC1InserCRE"));
DataTable dtCurrentTable = (DataTable)ViewState["CurrentTable"];
for (int i = 0; i <= (count - 1); i++)
{
drCurrentRow = dtCurrentTable.NewRow();
dtCurrentTable.Rows.Add(drCurrentRow);
}
gvCREInfo.DataSource = dtCurrentTable;
gvCREInfo.DataBind();
}
#endregion
}
当我运行此代码正常工作时，我更改了第一个下拉列表 它会拉出数据并绑定到第二个，就像明智的第三个一样。但是当我点击添加按钮时，选择的数据在第一行和第二行控件中丢失而不是数据。如何保留现有的选定数据并加载用户控制有了数据，它不应该丢失数据事件。请帮助我解决这个问题。 ！[在此输入图像说明] [1]
