JavaScript Examples Bible - UserWorks Technologies

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JavaScript Examples Bible: The Essential Companion to JavaScript Bible
Example
If you want to turn off buffering for an entire page, include the following statement
at the beginning of your script statements:
window.offscreenBuffering = false
onerror
windowObject.onerror
NN2 NN3 NN4 NN6 IE3/J1 IE3/J2 IE4 IE5 IE5.5
Compatibility ✓ ✓ ✓ ✓ ✓ ✓
Example
In Listing 16-10, one button triggers a script that contains an error. I’ve added an
error-handling function to process the error so that it opens a separate window and
fills in a textarea form element (see Figure 2-2). If you load Listing 16-10 in NN6,
some of the reporting categories report “undefined” because the browser unfortunately
does not pass error properties to the handleError() function. A Submit
button is also provided to mail the bug information to a support center e-mail
address — an example of how to handle the occurrence of a bug in your scripts.
Listing 16-10: Controlling Script Errors
Error Dialog Control
// function with invalid variable value
function goWrong() {
var x = fred
}
// turn off error dialogs
function errOff() {
window.onerror = doNothing
}
// turn on error dialogs with hard reload
function errOn() {
window.onerror = handleError
}
// assign default error handler
window.onerror = handleError
// error handler when errors are turned off...prevents error dialog
function doNothing() {return true}
function handleError(msg, URL, lineNum) {
var errWind = window.open(“”,”errors”,”HEIGHT=270,WIDTH=400”)
var wintxt = “”