This demo application shows how to upload multiple files in several threads concurrently.
The application highlights the following features:
To find information about how this demo is implemented using a specific platform, see the Samples by Platforms topic.
Note that concurrent upload and advanced details view are not yet supported in the Java version of Image Uploader. It will perform sequential upload and show standard progress dialog.
Sending several files in parallel reduces the total time of upload. To specify that the upload
should be performed using a number of concurrent connections, change the MaxConnectionCount property. Its value sets the
upper limit to the amount of HTTP threads (in this demo,
You can also specify that the files should be sent to several servers to distribute the load between them. For that, add required URLs to the value of the Action property, as it can take a semicolon-separated list of URLs. In this sample, the same server and page are used for all cases, but you can specify addresses pointing to different servers. For more details about the concurrent upload, see the Uploading Files Sequentially and Concurrently topic.
Conditions for automatic connection recovery are specified using the AutoRecoverTimeOut and AutoRecoverMaxTriesCount properties. For more details about connection recovery, see the Configuring Automatic Upload Recovery topic.
Figure 1. Advanced details view in the ActiveX version.
To specify the advanced details view, set the UploadView property to AdvancedDetails. The AdvancedDetailsPreviewThumbnailSize property is used to define the size of thumbnails in the list. For more details on this view mode, see the View Modes topic.
As this view provides its own progress bar for each image, the SilentMode is set to
specifying that the standard progress bar should not be shown. See the Adding a Custom Progress Bar topic for more details about working
with progress bars.
To stop all the uploads at once, the Stop button is provided. It is displayed when the upload is in progress and is hidden otherwise. Whether it should be displayed or hidden, it is determined in the BeforeUpload event handler.
To complete the upload started by Image Uploader, some actions
on the server side should be performed. The upload script of this application is almost equivalent to
the one of the Basic Demo Sample. The
only difference is that now images are sent in several batches, and, therefore, only POST fields with
index 1 (such as
FileName_1, etc.) are