ASP.NET DropDownList with XML Databinding

最後更新：2018-12-05 來源：互聯網

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First, this individual's XML file looked like this:
<?xml version="1.0" encoding="utf-8" ?>
<companytype>
<option value="Agricultural" name="Agricultural" />
<option value="Apparel" name="Apparel" />
<option value="Beverages" name="Beverages" />
<option value="Building Products" name="Building Products" />
</companytype>
Obviously, this looks more like the HTML you'd have in the actual listbox itself, and doesn't lend itself well to databinding. So the first thing I did was rewrite the XML so that it could be loaded into a DataSet and used more efficiently. Following is the revised code for "Xmldroplist.xml":
<?xml version="1.0" encoding="utf-8" ?>
<companytypes>
<companytype>
<value>Agricultural</value>
<name>Agricultural</name>
</companytype>
<companytype>
<value>Apparel</value>
<name>Apparel</name>
</companytype>
<companytype>
<value>Beverages</value>
<name>Beverages</name>
</companytype>
<companytype>
<value>Building Products</value>
<name>Building Products</name>
</companytype>
</companytypes>
Finally, I pieced together the most basic code to create the server control on the page, load the XML into a DataSet, and use dynamic databinding to populate the dropdown listbox. Following is the code for "XMLDropDownList.aspx":
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Xml" %>
<%@ Import Namespace="System.Xml.XPath" %>
<%@ Import Namespace="System.Xml.Xsl" %>
<%@ Import Namespace="System.IO" %>
<script language="C#" runat="Server">
void Page_Load(object sender, EventArgs e) {
if (!IsPostBack) {
BindDropDown();
}
}

void BindDropDown() {
string url = "http://localhost/ASP.NET/xmldroplist.xml";
DataSet ds = new DataSet();
ds.ReadXml(url);
customers.DataSource =ds.Tables[0];
customers.DataTextField =ds.Tables[0].Columns[0].ToString();
customers.DataValueField=ds.Tables[0].Columns[1].ToString();
customers.DataBind();
// Next 2 lines show way to set select item text and value...
//customers.Items.Insert(0, new ListItem("TestValue")) ;
//customers.Items[0].Value="84";
// Next line shows another way but using an existing item...
// customers.SelectedIndex=2;

}
</script>
<html>
<body bgcolor="#ffffff">
<form runat="server" ID="Form1">
<b>Select a Company Type to View:</b>
<asp:DropDownList id="customers" runat="server" />
</form>
</body>
</html>
When you run this page you'll get your dropdown listbox with all the values in it, and if you view source you'll see that both the DataTextField and the DataValueField properties have been translated into their proper places in each <option> element.

本文章原先以中文撰寫並發佈於 aliyun.com，亦設英文版本，僅作資訊用途。本網站不對文章的準確性，完整性或可靠性或其任何翻譯作出任何明示或暗示的陳述或保證。如對該文章有任何疑慮或投訴，請傳送電郵至 info-contact@alibabacloud.com 並提供相關疑慮或投訴的詳細說明。職員會於 5 個工作天內與您聯絡，一經驗證之後，即會刪除該侵權內容。

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