Form Processing

Your application will likely need to accept data from the user. Forms allow you to do just that. Forms can be submitted in one of two methods (GET and POST), and this server supports both.

The GET method appends the data to the end of the URI. You'll see this data following the question mark (?) in your browser's address bar. For Microchip's embedded server, this data is limited to around 80 bytes. However, this sort of submission is generally easier to process. Data sent via GET is automatically decoded, and stored in the array curHTTP.data. Your application will handle the data in the HTTPExecuteGet callback. The functions HTTPGetArg and HTTPGetROMArg provide an easy method to retrieve submitted values for processing.

As an example, this GET form controls several LEDs on the demo board:

5:   4:   3:   2:   1:  

Exercise: Modify this form to support LED 5.

The POST method submits the data after the request headers are sent. This allows the data to be virtually unlimited in length, as long as your application can process it in chunks. However, your application must manage the receipt of data, so it is generally more complicated.

As an example, this POST form sets the text shown on the LCD display: