The main form provides the user interface for the JumpStart application and consists of four elements.
Interface Element | Description |
---|---|
Text1 | A text box for entering the file name of the file to parse. |
Command1 | A button to start the parse process. |
Command2 | A button to exit the application. |
Text2 | A text box that displays the results of the parse operation. |
In addition to providing the interface elements, the main form also provides code that creates the required instances of the classes and starts the parse process.
To | The main form uses this code |
---|---|
Create an instance of the reader (SAXXMLReader ) |
Dim reader As New SAXXMLReader |
Create an instance of ContentHandlerImpl and set it to receive events from the reader |
Dim contentHandler As New ContentHandlerImpl Set reader.contentHandler = contentHandler |
Create an instance of ErrorHandlerImpl and set it to receive events from the reader |
Dim errorHandler As New ErrorHandlerImpl Set reader.errorHandler = errorHandler |
Start the parse process | reader.parseURL (Text1.text) |
The following is the complete code for the main form of the JumpStart application.
Option Explicit Private Sub Command1_Click() Dim reader As New SAXXMLReader 'Reads the XML document Dim contentHandler As New ContentHandlerImpl 'Receives parsing events Dim errorHandler As New ErrorHandlerImpl 'Receive error events Text2.text = "" Set reader.contentHandler = contentHandler 'They work together Set reader.errorHandler = errorHandler 'They also work together On Error GoTo 10 reader.parseURL (Text1.text) 'Parse the document Exit Sub 'That's all, folks! 10: Text2.text = Text2.text & "*** Error *** " & Err.Number _ & " : " & Err.Description End Sub Private Sub Command2_Click() End End Sub
The Exit Sub
and line marked 10:
are required only if you want to handle processing outside the ErrorHandler
. Otherwise, you can use On Error Resume Next
.
To run the JumpStart application
You can use this introduction to the Simple API for XML (SAX2) as a starting point for writing your own applications. For more information about the Microsoft® XML Core Services (MSXML) 5.0 for Microsoft Office implementation of the SAX2 interfaces, see the SAX2 Reference.