wcSetEventHandler( )

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Specifies which function is called when a given event occurs.

Example

returnCode = wcSetEventHandler(cntrlHandle, "timeoutHandler", hndlTimeout);

Syntax

int wcSetEventHandler(void *controlHandle, 
                      char *handlerName, 
                      int (*function)() )

controlHandle	The handle to the control structure.
handlerName	The name of the event handler.
function	A pointer to the function to be called to handle the event. Declare the function as follows: int function(void *wcp)

Returns

0	Success.
Error code	Failure or exception. For a list of possible error codes, see Error Messages.

Tips

Typically used with the <?MIEVENT> AppPage tag.
You might have several MIEVENT tags and several corresponding calls to wcSetEventHandler( ). You do not have to call wcSetEventHandler( ) in same order that the corresponding MIEVENT tags occur in the AppPage.
You can set up to 30 event handlers with different event names.

Program Example

In the following example, an event handler function runs a query to populate a list box in the HTML page.

/* Declare the event handling function */
int nameList(controlHandle)
	void *controlHandle;
{
	WebSelectList(cntrlHandle, "select last_name from customers", 
		"NAME=last&VALUE=selectList1", NULL);
}

int requestLoop(controlHandle)
	void *controlHandle;
{
	char *pageText;
	wcConOpen(controlHandle, 0);

	/* Associate nameList( ) with the "List" event */
	wcSetEventHandler(controlHandle, "List", nameList);

	/* Load and explode the AppPage */
	wcLoad(controlHandle, "page", &pageText);
	WebExplode(controlHandle, pageText, NULL);
	wcConClose(controlHandle);
}

The nameList( ) function is called when WebExplode( ) encounters the following tag in the AppPage:

<HTML>
<BODY<
...
<?MIEVENT NAME="List">
...
</HTML>
</BODY<