Image exists?

[Dennis Allen]

Hi. I've been trying to write Javascript code that checking if an image
exists. If it doesn't exist, I want to load a known image. I've tried:

if (document.images) {
var tester=new Image() // public variable
tester.onload="cImg('good')"
tester.onerror="cImg('bad')"
tester.src="http://www.temp.com/image.jpg"
}

function cImg(flg) {
if (flg == "good") {
document.images.main.alt = "Image is good"
document.images.main.src = "http://www.temp.com/image.jpg"
} else {
document.images.main.alt = "Known image"
document.images.main.src = "image.jpg"
}
}

Problem. As far as I can see, the onload and onerror don't fire.
Whether the image exists or not. At least in my IE6. What's the
problem? I've tried document.images.main.onload and onerror directly,
nothing. Any help is appreciated...Dennis

[Evertjan.]

Dennis Allen wrote on 19 mrt 2005 in comp.lang.javascript:

if (document.images) {
var tester=new Image() // public variable
tester.onload="cImg('good')"
tester.onerror="cImg('bad')"
tester.src="http://www.temp.com/image.jpg"
}

function cImg(flg) {
if (flg == "good") {
document.images.main.alt = "Image is good"
document.images.main.src = "http://www.temp.com/image.jpg"
} else {
document.images.main.alt = "Known image"
document.images.main.src = "image.jpg"
}
}

Problem. As far as I can see, the onload and onerror don't fire.
Whether the image exists or not. At least in my IE6. What's the
problem? I've tried document.images.main.onload and onerror directly,
nothing. Any help is appreciated...Dennis

Try this:

function good(){
alert('good')
}

function bad(){
alert('bad')
}

var tester=new Image() // public variable
tester.onload=good
tester.onerror=bad

tester.src="http://www.temp.com/image.jpg"

--
Evertjan.
The Netherlands.
(Replace all crosses with dots in my emailaddress)

[Dennis Allen]

Ah. onclick, onerror, onload can't be a string. Must call the function
directly. Thanks...Dennis

"Evertjan." <ex**************@interxnl.net> wrote in message
news:Xn********************@194.109.133.29...

Dennis Allen wrote on 19 mrt 2005 in comp.lang.javascript:

if (document.images) {
var tester=new Image() // public variable
tester.onload="cImg('good')"
tester.onerror="cImg('bad')"
tester.src="http://www.temp.com/image.jpg"
}

function cImg(flg) {
if (flg == "good") {
document.images.main.alt = "Image is good"
document.images.main.src = "http://www.temp.com/image.jpg"
} else {
document.images.main.alt = "Known image"
document.images.main.src = "image.jpg"
}
}

Problem. As far as I can see, the onload and onerror don't fire.
Whether the image exists or not. At least in my IE6. What's the
problem? I've tried document.images.main.onload and onerror
directly,
nothing. Any help is appreciated...Dennis

Try this:

function good(){
alert('good')
}

function bad(){
alert('bad')
}

var tester=new Image() // public variable
tester.onload=good
tester.onerror=bad

tester.src="http://www.temp.com/image.jpg"

--
Evertjan.
The Netherlands.
(Replace all crosses with dots in my emailaddress)

[Dennis Allen]

Oops. Here's example:

var tester=new Image()
tester.onload=function() {cImg('good')}
tester.onerror=function() {cImg('bad')}
tester.src="http://www.temp.com/image.jpg"