C# 设置下拉列表选定索引
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Setting dropdownlist selected index
提问by whoadityanawandar
I have a dropdownlist with country names in alphabetical order. I want the dropdown to have (show) India as the default value always. I don't want to set the selected index with a constant because other countries may be added to the list later. How can set the index to "India"?
我有一个按字母顺序排列的国家名称下拉列表。我希望下拉菜单始终将（显示）印度作为默认值。我不想将选定的索引设置为常量，因为稍后可能会将其他国家/地区添加到列表中。如何将索引设置为“印度”？
ddlCountryCode.DataSource = ds1.Tables["AUser"];
ddlCountryCode.DataTextField = "CountryCode";
ddlCountryCode.SelectedIndex =
ddlCountryCode.Items.IndexOf(ddlCountryCode.Items.FindByText("India(+91)"));
ddlCountryCode.DataBind();
doesnt work...
不起作用...
回答by Civa
Select Index after DataBind(). Data Bind Binds Items in 'ddlCountryCode.Items' So you can Select index of 'india' one items exists with ddlCountryCode.
在 DataBind() 之后选择 Index。数据绑定绑定“ddlCountryCode.Items”中的项目，因此您可以选择“印度”的索引，其中一项存在于 ddlCountryCode。
DropdownList1.Items is a list so u can use IndexOf()
ddlCountryCode.DataSource = ds1.Tables["AUser"];
ddlCountryCode.DataTextField = "CountryCode";
ddlCountryCode.DataBind();
ddlCountryCode.SelectedIndex =
ddlCountryCode.Items.IndexOf(ddlCountryCode.Items.FindByText("India(+91)"));
回答by ????
You can use like this
你可以这样使用
DropdownList1.SelectedIndex =
DropdownList1.Items.IndexOf(DropdownList1.Items.FindByValue(strText));
or
或者
DropdownList1.SelectedIndex =
DropdownList1.Items.IndexOf(DropdownList1.Items.FindByText(strText));
References
Setting dropdownlist selecteditem programmatically
Edit 1
编辑 1
Change the sequence of your code
更改代码的顺序
ddlCountryCode.DataSource = ds1.Tables["AUser"];
ddlCountryCode.DataTextField = "CountryCode";
ddlCountryCode.DataBind();
ddlCountryCode.SelectedIndex =
ddlCountryCode.Items.IndexOf(ddlCountryCode.Items.FindByText("India(+91)"));
回答by Pratik Mehta
DropDownList1.SelectedValue = "India";
