Overcoming the URL Length Restriction

Many web browsers have a limit of two thousand characters for a URL request string. The embed tag for an SVG object has a limit of 256 characters. Both of these limitations directly impact the HTTP request method.

Important: Because of the nature of JavaScript, the JavaScript PopChart Embedder also has this limitation.

Most of the time, your HTTP request strings will be well under two thousand characters. However, the SVG limitation can be difficult to get around, especially when you have a large amount of data. For this reason, we recommend using the PopChart Embedder.

If you are graphing a large amount of data and don't want to use the PopChart Embedder, you will need to remove the data from the URL request string. To do this, you can try the following options: Server Command Files and Loading Data Files.

Server Command Files

A server command file is simply a file that contains nothing but a server command string. It can reside either on the computer running PopChart Server, or on a separate computer. It can also be generated dynamically by a web application (this process is known as app-server callback).

Important: Do not URL-encode a server command file.

You can load a server command file with the @_LOADREQUEST server command. For example, to load the server command file examples/command/command1.txt, use the following server command:

@_LOADREQUESTexamples/command/command1.txt

For more information on server command files, refer to "Server Command Files" on page 6-13.

Loading Data Files

You can also get around the URL length restriction by storing all of your data in data files, located either on the computer running PopChart Server, or on a separate computer. Your data files can also be generated dynamically by a web application (this process is known as app-server callback).

For information about this, read Chapter 6, "Sending Dynamic Data to PopChart Server."

Be sure to use the PCScript graph. LoadFile() method to load data files.

One command not mentioned in that chapter is the @_LOADPCXML server command, which allows you to load PopChart XML files. For example, to load the examples/pcxml/pcxml1.xml file, use the following server command:

@_LOADPCXMLexamples/pcxml/p_data1.xml