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//------------------------------------------------------------------------------
// <copyright file="HtmlInputFile.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
/*
* HtmlInputFile.cs
*
* Copyright (c) 2000 Microsoft Corporation
*/
namespace System.Web.UI.HtmlControls {
using System;
using System.Collections;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Globalization;
using System.Web;
using System.Web.UI;
using System.Security.Permissions;
/// <devdoc>
/// <para>
/// The <see langword='HtmlInputFile'/> class defines the
/// methods, properties, and events for the <see langword='HtmlInputFile'/> control. This class allows
/// programmatic access to the HTML <input type= file> element on the server.
/// It provides access to the stream, as well as a useful SaveAs functionality
/// provided by the <see cref='System.Web.UI.HtmlControls.HtmlInputFile.PostedFile'/>
/// property.
/// </para>
/// <note type="caution">
/// This class only works if the
/// HtmlForm.Enctype property is set to "multipart/form-data".
/// Also, it does not maintain its
/// state across multiple round trips between browser and server. If the user sets
/// this value after a round trip, the value is lost.
/// </note>
/// </devdoc>
[
ValidationProperty("Value")
]
public class HtmlInputFile : HtmlInputControl, IPostBackDataHandler {
/*
* Creates an intrinsic Html INPUT type=file control.
*/
/// <devdoc>
/// <para>Initializes a new instance of the <see cref='System.Web.UI.HtmlControls.HtmlInputFile'/> class.</para>
/// </devdoc>
public HtmlInputFile() : base("file") {
}
/*
* Accept type property.
*/
/// <devdoc>
/// <para>
/// Gets
/// or sets a comma-separated list of MIME encodings that
/// can be used to constrain the file types that the browser lets the user
/// select. For example, to restrict the
/// selection to images, the accept value image/* should be specified.
/// </para>
/// </devdoc>
[
WebCategory("Behavior"),
DefaultValue(""),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public string Accept {
get {
string s = Attributes["accept"];
return((s != null) ? s : String.Empty);
}
set {
Attributes["accept"] = MapStringAttributeToString(value);
}
}
/*
* The property for the maximum characters allowed.
*/
/// <devdoc>
/// <para>
/// Gets or sets the
/// maximum length of the file path of the file to upload
/// from the client machine.
/// </para>
/// </devdoc>
[
WebCategory("Behavior"),
DefaultValue(""),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public int MaxLength {
get {
string s = Attributes["maxlength"];
return((s != null) ? Int32.Parse(s, CultureInfo.InvariantCulture) : -1);
}
set {
Attributes["maxlength"] = MapIntegerAttributeToString(value);
}
}
/*
* PostedFile property.
*/
/// <devdoc>
/// <para>Gets access to the uploaded file specified by a client.</para>
/// </devdoc>
[
WebCategory("Default"),
DefaultValue(""),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public HttpPostedFile PostedFile {
get { return Context.Request.Files[RenderedNameAttribute];}
}
/*
* The property for the width in characters.
*/
/// <devdoc>
/// <para>Gets or sets the width of the file-path text box that the
/// browser displays when the <see cref='System.Web.UI.HtmlControls.HtmlInputFile'/>
/// control is used on a page.</para>
/// </devdoc>
[
WebCategory("Appearance"),
DefaultValue(-1),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public int Size {
get {
string s = Attributes["size"];
return((s != null) ? Int32.Parse(s, CultureInfo.InvariantCulture) : -1);
}
set {
Attributes["size"] = MapIntegerAttributeToString(value);
}
}
// ASURT 122262 : The value property isn't submitted back to us when the a page
// containing this control postsback, so required field validators are broken
// (value would contain the empty string). To fix this, we return the filename.
[
Browsable(false)
]
public override string Value {
get {
HttpPostedFile postedFile = PostedFile;
if (postedFile != null) {
return postedFile.FileName;
}
return String.Empty;
}
set {
// Throw here because setting the value on this tag has no effect on the
// rendering behavior and since we're always returning the posted file's
// filename, we don't want to get into a situation where the user
// sets a value and does not get back that value.
throw new NotSupportedException(SR.GetString(SR.Value_Set_Not_Supported, this.GetType().Name));
}
}
/*
* Method of IPostBackDataHandler interface to process posted data.
*/
/// <internalonly/>
bool IPostBackDataHandler.LoadPostData(string postDataKey, NameValueCollection postCollection) {
return LoadPostData(postDataKey, postCollection);
}
protected virtual bool LoadPostData(string postDataKey, NameValueCollection postCollection) {
return false;
}
/*
* Method of IPostBackDataHandler interface which is invoked whenever
* posted data for a control has changed. RadioButton fires an
* OnServerChange event.
*/
/// <internalonly/>
void IPostBackDataHandler.RaisePostDataChangedEvent() {
RaisePostDataChangedEvent();
}
protected virtual void RaisePostDataChangedEvent() {
}
/// <devdoc>
/// <para>Raises the <see langword='PreRender'/> event. This method uses event arguments
/// to pass the event data to the control.</para>
/// </devdoc>
protected internal override void OnPreRender(EventArgs e) {
base.OnPreRender(e);
// ASURT 35328: use multipart encoding if no encoding is currently specified
HtmlForm form = Page.Form;
if (form != null && form.Enctype.Length == 0) {
form.Enctype = "multipart/form-data";
}
}
}
}
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