See the ConvertedFile. Name property description for a full list of possible suffixes. On the configuring step we specified the UploadSettings. RedirectUrl property to the "gallery. It would be convenient to display uploaded images here. See comments in the source code below.
You may run this image gallery application on your server. To do this, just paste source code to default. NET Topics. Upload Suite Overview What's New? NET Web Form. Simplification of server upload script. The control gets data sent from the client, parses it, and provides typed access to this data server-side.
Autosave of uploaded files. NET allows you to create your upload solution without writing a line of code. NET to the toolbox: Right-click on the tab of toolbox where you want to add this control and select Choose Items Find the Uploader in the. NET Framework Components tab. If you cannot find this component, click Browse Set this page as a start page. To do it, right-click this page default.
GetFileName Container. Therefore as you can make use of COM objects in. NET Framework as if they are. NET Framework uses inheritance concept, it is possible to inherit objects from these controls to any language supported by. NET Framework. Though you can design or create your own controls, you have to inherit from System. Control to make use of the services provided by this class. There are some new properties that you cannot view in Visual Basic but can see in Visual Basic. They are accessible description, accessible name, anchor, and dock.
If these are the newly added ones, then there are some ActiveX Controls such as Lines and Shapes that are not available for Windows Forms. Instead of Lines and Shapes, in. ActiveX Controls also have some properties that are commonly known as extender properties such as Left, Right, and Visible. The Windows Forms engine replaces these extender properties with its own set of properties. Thus, Windows Forms now have both extender properties and inherited properties. The Windows Forms engine replaces the extender properties by creating a wrapper for each of the ActiveX control.
After a user clicks the Upload File button, the form data will be sent to the server. The code of the Upload File button click handler should look like this:. This event handler checks if any file has been specified, tries to save it to the uploads folder, and displays a message indicating whether the file has been saved successfully.
Note that the FileUpload1 name is similar to the FileUpload id attribute in the client form discussed above. When adding simple upload to you web application do not forget that it does not protect your server from the malicious files that a user can upload. There are several security concerns which can help you to consider whether accept an uploaded file. For example, you can control the type of uploaded file by checking the extension which can be easily spoofed or the correct "magic number" in the file header.
To upload a single file at a time is very easy, but it in rare use nowadays. If you are going to design your own site, most likely you will need to upload several files at a time. The most important advantage of the FileUpload server control is the support of multiple file upload. To enable it, just slightly modify the client application considered above. However, you should understand that the multiple upload feature works correctly only in browsers that support HTML5.
The only change required in the client application considered above is adding the AllowMultiple property which specifies whether multiple files can be selected for upload:.
Now the handler code may look as follows:. As a result, you will get the same upload interface, but the text box displays the number of selected files:. The FileUpload control is great when you only upload a few small files, but it has several disadvantages:.
Fortunately, some third party uploaders are partially free of these concerns. Nowadays all popular browsers support the Flash or newer HTML5 platform, which allows the creating of advanced file upload using Flex or JavaScript respectively.
Thus, there are a lot of third-party uploaders. These uploaders are very good at multiple file upload, provide a simple interface, and are supported by a big community of developers. However, the following tasks cannot be solved by these uploaders:. How to upload files in ASP. NET Nowadays you may find file upload in almost every website — from forums that allow users to upload photos for their avatars, to online auctions where users can create galleries with a lot of images.
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