C# DropDownList 将所选项目设置为 true
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DropDownList set selected item to true
提问by sharon Hwk
I have added DropDownList in ASP.net.
我在 ASP.net 中添加了 DropDownList。
<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged" >
<asp:ListItem Text="Name" Value="jsh" Selected="true" />
<asp:ListItem Text="hhh" Value="sds"/>
</asp:DropDownList>
Instead on saying Selected="true"in ASP.net i want to set the selected item using C# inside the
而不是Selected="true"在 ASP.net 中说我想在里面使用 C# 设置所选项目
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList1 // THE SELECTED ITEM NEEDS TO BE SET TO TRUE
Response.Redirect(Request.RawUrl);
}
UPDATE
更新
<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged" OnTextChanged="DropDownList1_onChanged">
</asp:DropDownList>
C#
C＃
protected void Page_Load(object sender, EventArgs e)
{
if(!Page.IsPostBack)
{
DropDownList1.Items.Add(new ListItem("En", "en-US"));
DropDownList1.Items.Add(new ListItem("Fr", "fr-FR"));
}
}
// I also copied InitializeCulture()
// 我也复制了 InitializeCulture()
protected override void InitializeCulture()
{
string Kultur = "en-US";
if (Session["lang"] != null)
{
Kultur = Session["lang"].ToString();
}
this.UICulture = Kultur;
this.Culture = Kultur;
base.InitializeCulture();
}
//
//
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList1.Items.FindByValue(DropDownList1.SelectedValue).Selected = true;
Response.Redirect(Request.RawUrl);
}
采纳答案by Prasad Kanaparthi
Actually, Your question doesnot make sence. If the user selected it, it is already selected. When you refresh the page the DropDownList1is again loading values. So you the DropDownList1selected item would be lost
其实，你的问题没有意义。如果用户选择了它，则它已经被选中。当您刷新页面时，DropDownList1将再次加载值。所以你DropDownList1选择的项目会丢失
You can do like this,
你可以这样做，
In aspxfile
在aspx文件中
<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged">
</asp:DropDownList>
In aspx.csfile
在aspx.cs文件中
protected void Page_Load(object sender, EventArgs e)
{
if(!Page.IsPostBack)
{
DropDownList1.Items.Add(new ListItem("Name", "jsh"));
DropDownList1.Items.Add(new ListItem("hhh", "sds"));
}
}
Below code is to select the item
下面的代码是选择项目
DropDownList1.Items.FindByValue(DropDownList1.SelectedValue).Selected = true;
or
或者
DropDownList1.Items.FindByText(DropDownList1.SelectedItem.Text).Selected = true;
or
或者
DropDownList1.SelectedItem.Selected = true;
回答by sreejithsdev
DropDownList1.SelectedValue = "value";
Or
DropDownList1.SelectedIndex= 1;
回答by Ashfaq Shaikh
you can also make selection in this way.
您也可以通过这种方式进行选择。
if (ddl.Items.FindByValue("value") != null && !string.IsNullOrEmpty("value"))
{
ddl.Items.FindByValue("value").Selected = true;
}
