ASP.NET.in.a.Nutshell.Second.Edition [Electronic resources]

G. andrew Duthie; matthew Macdonald

نسخه متنی -صفحه : 873/ 547
نمايش فراداده

HtmlInputFiledisposable

System.Web.UI.HtmlControls (system.web.dll)class

This class represents the HTML <input type=file> tag, which allows the user to upload a binary or text file. This control is rendered as a text box with a paired Browse button. The Browse button opens a standard file selection dialog box. The chosen file is not transmitted until the form is posted to the server (usually through a submit button). You can then add code in the event handler of this button to save or otherwise manipulate the file using the PostedFile property, which provides a System.Web.HttpPostedFile object.

You can use the HtmlInputFile property to specify a comma-separated list of MIME file types that your control will accept. You can also change the maximum path length for the filename (MaxLength) and the width of the file path text box (Size). The HtmlForm.Enctype property of the containing form must be set to multipart/form-data to allow file uploads. You can limit the maximum size of file uploads using the maxRequestLength setting in the web.config file. By default, file uploads larger than 4096 KB will not be allowed.

public class 

HtmlInputFile : HtmlInputControl, System.Web.UI.IPostBackDataHandler { // Public Constructors public

HtmlInputFile ( ); // Public Instance Properties public string

Accept {set; get; } public int

MaxLength {set; get; } public HttpPostedFile

PostedFile {get; } public int

Size {set; get; } public override string

Value {set; get; } // overrides HtmlInputControl // Protected Instance Methods protected override void

OnPreRender (EventArgs

e ); // overrides System.Web.UI.Control }

Hierarchy

System.Object System.Web.UI.Control(System.ComponentModel.IComponent, System.IDisposable, System.Web.UI.IParserAccessor, System.Web.UI.IDataBindingsAccessor) HtmlControl(System.Web.UI.IAttributeAccessor) HtmlInputControl HtmlInputFile(System.Web.UI.IPostBackDataHandler)