Asp.net WebForm 获取当前页面提交的所有文件的方法
Context.Request.Files
Context.Request.Files.GetMultiple(Context.Request.Files.Keys[0]);
获取文件属性和保存文件
for (int i = 0; i < Context.Request.Files.Count; i++)
{
var file = Context.Request.Files[i];
var length= file.ContentLength;
var type = file.ContentType;
var name = file.FileName;
var stream = file.InputStream;
file.SaveAs("filePath");
}
We need to add <httpModules> to Web.config that make sure SaveAs Method can work
<system.web> <httpRuntime executionTimeout="500" maxRequestLength="153600" requestLengthDiskThreshold="153600"/> </system.web>
FileUpload 源码中的SaveAs 也使用 Context.Request.Files 的SaveAs()：
//------------------------------------------------------------------------------
// <copyright file="FileUpload.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
//
namespace System.Web.UI.WebControls {
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Linq;
using System.IO;
using System.Text;
using System.Web.UI.HtmlControls;
/// <devdoc>
/// Displays a text box and browse button that allows the user to select a file for uploading.
/// </devdoc>
[ControlValueProperty("FileBytes")]
[ValidationProperty("FileName")]
[Designer("System.Web.UI.Design.WebControls.PreviewControlDesigner, " + AssemblyRef.SystemDesign)]
public class FileUpload : WebControl {
private static readonly IList<HttpPostedFile> _emptyFileCollection = new HttpPostedFile[0];
private IList<HttpPostedFile> _postedFiles;
public FileUpload() : base(HtmlTextWriterTag.Input) {
}
[
Browsable(true),
DefaultValue(false),
WebCategory("Behavior"),
WebSysDescription(SR.FileUpload_AllowMultiple)
]
public virtual bool AllowMultiple {
get {
object o = ViewState["AllowMultiple"];
return (o != null) ? (bool)o : false;
}
set {
ViewState["AllowMultiple"] = value;
}
}
/// <devdoc>
/// Gets the byte contents of the uploaded file. Needed for ControlParameters and templatized
/// ImageFields.
/// </devdoc>
[
Bindable(true),
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public byte[] FileBytes {
get {
Stream fileStream = FileContent;
if (fileStream != null && fileStream != Stream.Null) {
long fileStreamLength = fileStream.Length;
BinaryReader reader = new BinaryReader(fileStream);
Byte[] completeImage = null;
if (fileStreamLength > Int32.MaxValue) {
throw new HttpException(SR.GetString(SR.FileUpload_StreamTooLong));
}
if (!fileStream.CanSeek) {
throw new HttpException(SR.GetString(SR.FileUpload_StreamNotSeekable));
}
int currentStreamPosition = (int)fileStream.Position;
int fileStreamIntLength = (int)fileStreamLength;
try {
fileStream.Seek(0, SeekOrigin.Begin);
completeImage = reader.ReadBytes(fileStreamIntLength);
}
finally {
// Don't close or dispose of the BinaryReader because doing so would close the stream.
// We want to put the stream back to the original position in case this getter is called again
// and the stream supports seeking, the bytes will be returned again.
fileStream.Seek(currentStreamPosition, SeekOrigin.Begin);
}
if (completeImage.Length != fileStreamIntLength) {
throw new HttpException(SR.GetString(SR.FileUpload_StreamLengthNotReached));
}
return completeImage;
}
return new byte[0];
}
}
/// <devdoc>
/// Gets the contents of the uploaded file.
/// </devdoc>
[
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public Stream FileContent {
get {
HttpPostedFile f = PostedFile;
if (f != null) {
return PostedFile.InputStream;
}
return Stream.Null;
}
}
/// <devdoc>
/// The name of the file on the client's computer, not including the path.
/// </devdoc>
[
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public string FileName {
get {
HttpPostedFile postedFile = PostedFile;
string fileName = string.Empty;
if (postedFile != null) {
string fullFileName = postedFile.FileName;
try {
// Some browsers (IE 6, Netscape 4) return the fully-qualified filename,
// like "C: empfoo.txt". The application writer is probably not interested
// in the client path, so we just return the filename part.
fileName = Path.GetFileName(fullFileName);
}
catch {
fileName = fullFileName;
}
}
return fileName;
}
}
/// <devdoc>
/// Whether or not a file was uploaded.
/// </devdoc>
[
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public bool HasFile {
get {
// Unfortunately returns false if a 0-byte file was uploaded, since we see a 0-byte
// file if the user entered nothing, an invalid filename, or a valid filename
// of a 0-byte file. We feel this scenario is uncommon.
HttpPostedFile f = PostedFile;
return f != null && f.ContentLength > 0;
}
}
/// <devdoc>
/// Whether or not at least 1 non-0-length file was uploaded.
/// </devdoc>
[
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public bool HasFiles {
get {
// Unfortunately returns false if a 0-byte file was uploaded, since we see a 0-byte
// file if the user entered nothing, an invalid filename, or a valid filename
// of a 0-byte file. We feel this scenario is uncommon.
return PostedFiles.Any(f => f.ContentLength > 0);
}
}
/// <devdoc>
/// Provides access to the underlying HttpPostedFile.
/// </devdoc>
[
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public HttpPostedFile PostedFile {
get {
if (Page != null && Page.IsPostBack) {
return Context.Request.Files[UniqueID];
}
return null;
}
}
[
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public IList<HttpPostedFile> PostedFiles {
get {
if (_postedFiles == null) {
IList<HttpPostedFile> result = _emptyFileCollection;
if (Page != null && Page.IsPostBack) {
result = Context.Request.Files.GetMultiple(UniqueID);
Debug.Assert(result != null);
}
_postedFiles = result;
}
return _postedFiles;
}
}
protected override void AddAttributesToRender(HtmlTextWriter writer) {
writer.AddAttribute(HtmlTextWriterAttribute.Type, "file");
if (AllowMultiple) {
writer.AddAttribute(HtmlTextWriterAttribute.Multiple, "multiple");
}
string uniqueID = UniqueID;
if (uniqueID != null) {
writer.AddAttribute(HtmlTextWriterAttribute.Name, uniqueID);
}
base.AddAttributesToRender(writer);
}
protected internal override void OnPreRender(EventArgs e) {
base.OnPreRender(e);
HtmlForm form = Page.Form;
if (form != null && form.Enctype.Length == 0) {
form.Enctype = "multipart/form-data";
}
}
protected internal override void Render(HtmlTextWriter writer) {
// Make sure we are in a form tag with runat=server.
if (Page != null) {
Page.VerifyRenderingInServerForm(this);
}
base.Render(writer);
}
/// <devdoc>
/// Initiates a utility method to save an uploaded file to disk.
/// </devdoc>
public void SaveAs(string filename) {
HttpPostedFile f = PostedFile;
if (f != null) {
f.SaveAs(filename);
}
}
}
}