HtmlInputFile.PostedFile 属性
定义
获取对由客户端指定的上载文件的访问。Gets access to the uploaded file specified by a client.
public:
property System::Web::HttpPostedFile ^ PostedFile { System::Web::HttpPostedFile ^ get(); };
public System.Web.HttpPostedFile PostedFile { get; }
member this.PostedFile : System.Web.HttpPostedFile
Public ReadOnly Property PostedFile As HttpPostedFile
属性值
HttpPostedFile,它访问要上载的文件。A HttpPostedFile that accesses the file to be uploaded.
示例
下面的代码示例演示如何使用 PostedFile 属性启动将文件传输到服务器的实用工具。The following code example demonstrates how to use the PostedFile property to initiate the utility that transfers the file to the server. 请注意,如果上载文件的大小(以字节为单位)超过了 ContentLength 属性的值,则不会上传该文件。Note that if the size of the uploaded file in bytes exceeds the value of the ContentLength property, the file is not uploaded. 要使此示例正常工作,需要 Temp 在计算机的驱动器 C 上创建一个名为的目录。For this example to work properly, you need to create a directory called Temp on your computer's drive C.
<%@ 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 Source, EventArgs e)
{
// Make sure a file was submitted.
if (Text1.Value == "")
{
Span1.InnerHtml = "Error: You must enter a file name.";
return;
}
// Save the file.
if (File1.PostedFile.ContentLength > 0)
{
try
{
File1.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() + ".";
}
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>HtmlInputFile Example</title>
</head>
<body>
<h3>HtmlInputFile Example</h3>
<form id="form1" enctype="multipart/form-data"
runat="server">
Select File to Upload:
<input id="File1"
type="file"
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 Source As Object, ByVal e As EventArgs)
' 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 File1.PostedFile.ContentLength > 0 Then
Try
File1.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
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>HtmlInputFile Example</title>
</head>
<body>
<h3>HtmlInputFile Example</h3>
<form id="form1" enctype="multipart/form-data"
runat="server">
Select File to Upload:
<input id="File1"
type="file"
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
浏览器安全限制阻止跨多个请求维护此值。Browser security restrictions prevent this value from being maintained across multiple requests.