HtmlInputFile 构造函数
定义
重要
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初始化 HtmlInputFile 类的新实例。
public:
HtmlInputFile();public HtmlInputFile ();Public Sub New ()示例
下面的代码示例演示如何创建 HtmlInputFile 类的新实例。 若要使此示例正常工作，需要在计算机的驱动器 C 上创建名为 Temp 的目录。
<%@ Page Language="C#" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void Button1_Click(object sender, EventArgs e)
{
// Get the HtmlInputFile control from the Controls collection
// of the PlaceHolder control.
HtmlInputFile file = (HtmlInputFile)Place.FindControl("File1");
// Make sure a file was submitted.
if (Text1.Value == "")
{
Span1.InnerHtml = "Error: You must enter a file name.";
return;
}
// Save the file.
if (file.PostedFile.ContentLength > 0)
{
try
{
file.PostedFile.SaveAs("c:\\temp\\" + Text1.Value);
Span1.InnerHtml = "File uploaded successfully to " +
"<b>c:\\temp\\" + Text1.Value + "</b> on the Web server.";
}
catch (Exception exc)
{
Span1.InnerHtml = "Error saving file <b>c:\\temp\\" +
Text1.Value + "</b><br />" + exc.ToString() + ".";
}
}
}
void Page_Load(object sender, EventArgs e)
{
// Create a new HtmlInputFile control.
HtmlInputFile file = new HtmlInputFile();
file.ID = "File1";
// Add the control to the Controls collection of the
// PlaceHolder control.
Place.Controls.Clear();
Place.Controls.Add(file);
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>HtmlInputFile Constructor Example</title>
</head>
<body>
<h3>HtmlInputFile Constructor Example</h3>
<form id="form1" enctype="multipart/form-data"
runat="server">
Specify the file to upload:
<asp:PlaceHolder id="Place"
runat="server"/>
<p>
Save as file name (no path):
<input id="Text1"
type="text"
runat="server" />
</p>
<p>
<span id="Span1"
style="font: 8pt verdana;"
runat="server" />
</p>
<p>
<input type="button"
id="Button1"
value="Upload"
onserverclick="Button1_Click"
runat="server" />
</p>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs)
' Get HtmlInputFile control from the Controls collection
' of the PlaceHolder control.
Dim file As HtmlInputFile = _
CType(Place.FindControl("File1"), HtmlInputFile)
' Make sure a file was submitted.
If Text1.Value = "" Then
Span1.InnerHtml = "Error: You must enter a file name."
Return
End If
' Save the file.
If file.PostedFile.ContentLength > 0 Then
Try
file.PostedFile.SaveAs(("c:\temp\" & Text1.Value))
Span1.InnerHtml = "File uploaded successfully to " & _
"<b>c:\temp\" & Text1.Value & "</b> on the Web server."
Catch exc As Exception
Span1.InnerHtml = "Error saving file <b>c:\temp\" & _
Text1.Value & "</b><br />" & exc.ToString() & "."
End Try
End If
End Sub
Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Create a new HtmlInputFile control.
Dim file As HtmlInputFile = New HtmlInputFile()
file.ID = "File1"
' Add the control to the Controls collection of the
' PlaceHolder control.
Place.Controls.Clear()
Place.Controls.Add(file)
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>HtmlInputFile Constructor Example</title>
</head>
<body>
<h3>HtmlInputFile Constructor Example</h3>
<form id="form1" enctype="multipart/form-data"
runat="server">
Specify the file to upload:
<asp:PlaceHolder id="Place"
runat="server"/>
<p>
Save as file name (no path):
<input id="Text1"
type="text"
runat="server" />
</p>
<p>
<span id="Span1"
style="font: 8pt verdana;"
runat="server" />
</p>
<p>
<input type="button"
id="Button1"
value="Upload"
onserverclick="Button1_Click"
runat="server" />
</p>
</form>
</body>
</html>
注解
使用此构造函数创建和初始化 类的新实例 HtmlInputFile 。
下表显示了 实例 HtmlInputFile的初始属性值。
| properties | 初始值 |
|---|---|
| Type | “file”文本字符串。 |
