XmlDataSource.Transforming 事件
定义
重要
一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。 对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。
将由 Transform 属性定义或由 TransformFile 属性标识的样式表应用到 XML 数据前发生。
public:
event EventHandler ^ Transforming;public event EventHandler Transforming;member this.Transforming : EventHandler Public Custom Event Transforming As EventHandler 事件类型
示例
下面的代码示例演示如何将 控件与 控件配合使用XmlDataSourceTreeView来显示转换后的 XML 数据。 XML 转换使用 属性指示的 TransformFile 样式表执行。 此外，样式表使用在运行时传递给 数据源控件的 XsltArgumentList 转换参数。 该代码示例演示如何通过使用自定义事件处理程序处理 Transforming 事件，将 对象传递给XsltArgumentList数据源控件。
<%@ Page Language="C#" %>
<%@ Import Namespace="System.Xml.Xsl" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
private void TransformEventHandler(object sender, EventArgs e) {
// Add a dynamic transformation argument.
DateTime d = new DateTime();
d = DateTime.Now.AddDays(20);
// Create an XsltArgumentList.
XsltArgumentList xslArg = new XsltArgumentList();
xslArg.AddParam("purchdate", "", d.ToShortDateString());
((XmlDataSource) sender).TransformArgumentList = xslArg;
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>ASP.NET Example</title>
</head>
<body>
<form id="form1" runat="server">
<asp:XmlDataSource
id="XmlDataSource1"
runat="server"
datafile="bookstore.xml"
transformfile="bookswithdiscount.xsl"
ontransforming="TransformEventHandler" />
<!- TreeView uses hierachical data, so the
XmlDataSource uses an XmlHierarchicalDataSourceView
when a TreeView is bound to it. -->
<asp:treeview
id="TreeView1"
runat="server"
datasourceid="XmlDataSource1">
<databindings>
<asp:treenodebinding Depth="1" datamember="genre"
textfield="name" valuefield="name"/>
<asp:treenodebinding depth="2" datamember="book"
textfield="title" valuefield="title"/>
<asp:treenodebinding depth="3" datamember="chapter"
textfield="name" valuefield="num"/>
</databindings>
</asp:treeview>
</form>
</body>
</html>
<%@ Page Language="VB" %>
<%@ Import Namespace="System.Xml.Xsl" %>
<script runat="server">
Private Sub TransformEventHandler(sender As Object, e as EventArgs)
' Add a dynamic transformation argument.
Dim d As New DateTime
d = DateTime.Now.AddDays(20)
'Create an XsltArgumentList.
Dim xslArg As XsltArgumentList = New XsltArgumentList
xslArg.AddParam("purchdate", "", d.ToShortDateString())
Dim aXmlDataSource as XmlDataSource = CType(sender, XmlDataSource)
aXmlDataSource.TransformArgumentList = xslArg
End Sub ' TransformEventHandler
</script>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>ASP.NET Example</title>
</head>
<body>
<form id="form1" runat="server">
<asp:xmldatasource
id="XmlDataSource1"
runat="server"
datafile="bookstore.xml"
transformfile="bookswithdiscount.xsl"
ontransforming="TransformEventHandler" />
<!- TreeView uses hierachical data, so the
XmlDataSource uses an XmlHierarchicalDataSourceView
when a TreeView is bound to it. -->
<asp:treeview
id="TreeView1"
runat="server"
datasourceid="XmlDataSource1">
<databindings>
<asp:treenodebinding depth="1" datamember="genre"
textfield="name" valuefield="name"/>
<asp:treenodebinding depth="2" datamember="book"
textfield="title" valuefield="title"/>
<asp:treenodebinding depth="3" datamember="chapter"
textfield="name" valuefield="num"/>
</databindings>
</asp:treeview>
</form>
</body>
</html>
代码示例中的 XML 文件具有以下数据：
<bookstore>
<genre name="fiction">
<book ISBN="0000000000">
<title>Secrets of Silicon Valley</title>
<price>12.95</price>
<chapters>
<chapter num="1" name="Introduction" />
<chapter num="2" name="Body" />
<chapter num="3" name="Conclusion" />
</chapters>
</book>
</genre>
<genre name="novel">
<book genre="novel" ISBN="1111111111">
<title>Straight Talk About Computers</title>
<price>24.95</price>
<chapters>
<chapter num="1" name="Introduction" />
<chapter num="2" name="Body" />
<chapter num="3" name="Conclusion" />
</chapters>
</book>
</genre>
</bookstore>
XML 数据的转换使用以下样式表执行：
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:param name="purchdate"/>
<xsl:template match="bookstore">
<bookstore>
<xsl:apply-templates select="genre"/>
</bookstore>
</xsl:template>
<xsl:template match="genre">
<genre>
<xsl:attribute name="name">
<xsl:value-of select="@name"/>
</xsl:attribute>
<xsl:apply-templates select="book"/>
</genre>
</xsl:template>
<xsl:template match="book">
<book>
<xsl:attribute name="ISBN">
<xsl:value-of select="@ISBN"/>
</xsl:attribute>
<xsl:attribute name="title">
<xsl:value-of select="title"/>
Price: <xsl:value-of select="price"/>
15% discount if purchased by: <xsl:value-of select="$purchdate"/>
</xsl:attribute>
<xsl:apply-templates select="chapters/chapter" />
</book>
</xsl:template>
<xsl:template match="chapter">
<chapter>
<xsl:attribute name="num">
<xsl:value-of select="@num"/>
</xsl:attribute>
<xsl:attribute name="name">
<xsl:value-of select="@name"/>
</xsl:attribute>
<xsl:apply-templates/>
</chapter>
</xsl:template>
</xsl:stylesheet>
注解
处理 事件以Transforming在控件执行 XML 转换之前XmlDataSource使用 XsltArgumentList 对象设置 TransformArgumentList 属性。
有关如何处理事件的详细信息，请参阅 处理和引发事件。
