Web Hosting Talk : Web Hosting Main Forums : Programming Discussion : Javascript Problem

[X-TechMedia]

I have a series of checkboxes and multiple select lists, that are used to choose which mailing lists to subscribe to.

The checkboxes are called mail[1], mail[2] etc
and the select boxes sel[1], sel[2] etc

I want it so that when i click on mail[1] it selects all the options in sel[1].

its called by onclick="DoAll('n')" (where n is the number, 1,2 etc)

Does anyone know why this isnt working?

function DoAll(id) {
if (document.action.mail[id].selected==true) {
	for(var i=0;i<document.action.sel[id].length;i++) {
		document.action.sel[i].selected=true;
	}
}

if (document.action.mail[id].selected==false) {
	for(var i=0;i<document.action.sel[id].length;i++) {
		document.action.sel[i].selected=false;
	}
}
}

[sasha]

i think you might need to refer to options as:
document.action.sel[id].options[i]

[Rich2k]

I wouldn't do it like that. Firstly all of your form elements should be in a form or they may not work in Netscape.

function DoAll(id) {
if (document.forms.formname.checkboxname[id].checked == true) {
	for(var i=0;i<document.forms.formname.selectname[id].length;i++) {
		document.forms.formname.selectname[id].optionname.selected = true;
	}
}
}

and then don't call it with DoAll['n'] but DoAll[n] as it's a numeric value.

obviously you need to replace the element and form names in the above

Remember for checkboxes you have to test for checked NOT selected

(Note: I haven't tested this so it may have errors)

[sasha]

... or like this




function DoAll(id) {
bl = document.action.sel[id] ;
if (document.action.mail[id].selected==true) {
for(var i=0;i<bl.options.length;i++) {
bl.options[i].selected=true;
}
}

[X-TechMedia]

Thanks people, i got it sorted in the end!

in case your intrested:

if (document.action.elements['mail['+ id +']'].checked==true) {
		for(var i=0;i<document.action.elements['sel['+ id +']'].length;i++) {
			document.action.elements['sel['+ id +']'].options[i].selected=true;
		}
	}
	
	if (document.action.elements['mail['+ id +']'].checked==false) {
		for(var i=0;i<document.action.elements['sel['+ id +']'].length;i++) {
			document.action.elements['sel['+ id +']'].options[i].selected=false;
		}
	}