Validate multiple checkboxes ok but fails for one

[mat41]

Hi there JS gurus, please help....

This code works well to validate multiple checkboxes that are all named the same which is what I want. The array of checkboxes is dynamic, sometime there will only be one. In this situation if I check this one checkbox it throws the 'You have not ticked any options....'. I would like checked = true to fire in this situation. Im having a headache of a time getting it to work. your help would be appreciated?

var checked = false;
var field = myForm.selectedDocs;
for(var j = 0; j < field.length; j++)
{
if(field[j].checked == true)
{
checked = true;
break;
}
}
if(!checked)
{
alert("You have not ticked any options. At least one must be selected to proceed!")
return false;
}

 

[vacunita]

You need to determine what you are getting from the selectedDocs element, and act accordingly.

When you have more than one input present you'll get a nodeList. (An Array of the inputs for all intents and purposes), but when you are dealing with a single element you get just that, an element, so the "length" property is meaningless as there is only one.

[tab][b][COLOR=#0000FF]var[/color][/b] field [COLOR=#990000]=[/color] myForm[COLOR=#990000].[/color]selectedDocs[COLOR=#990000];[/color]
[tab][b][COLOR=#0000FF]if[/color][/b][COLOR=#990000]([/color]field[COLOR=#990000].[/color][b][COLOR=#000000]toString[/color][/b][COLOR=#990000]()[/color] [COLOR=#990000]==[/color] [COLOR=#FF0000]'[object NodeList]'[/color][COLOR=#990000])[/color]
[tab][COLOR=#FF0000]{[/color]
[tab][tab][tab][i][COLOR=#9A1900]//Do the for loop here...[/color][/i]
[tab][COLOR=#FF0000]}[/color]
[tab][b][COLOR=#0000FF]else[/color][/b] [b][COLOR=#0000FF]if[/color][/b][COLOR=#990000]([/color]field[COLOR=#990000].[/color][b][COLOR=#000000]toString[/color][/b][COLOR=#990000]()[/color] [COLOR=#990000]==[/color] [COLOR=#FF0000]'[object HTMLInputElement]'[/color][COLOR=#990000])[/color]
[tab][COLOR=#FF0000]{[/color]
[tab][tab][tab][i][COLOR=#9A1900]//Since its a single element, just check its "checked" property to see if its checked or not.[/color][/i]
[tab][tab][tab][b][COLOR=#0000FF]if[/color][/b][COLOR=#990000]([/color]field[COLOR=#990000].[/color]checked[COLOR=#990000]==[/color][b][COLOR=#0000FF]true[/color][/b][COLOR=#990000])[/color]
[tab][tab][tab][COLOR=#FF0000]{[/color]
[tab][tab][tab][tab][i][COLOR=#9A1900]//Do whatever[/color][/i]
[tab][tab][tab][COLOR=#FF0000]}[/color]
[tab][COLOR=#FF0000]}[/color]

----------------------------------
Phil AKA Vacunita
----------------------------------
Ignorance is not necessarily Bliss, case in point:
Unknown has caused an Unknown Error on Unknown and must be shutdown to prevent damage to Unknown.

Web & Tech

 

[mat41]

Hi there - Sorry I missed this post somehow. Thank you for your answer however I am confused what to use in place of [object NodeList] and [object HTMLInputElement]

Thanking you

 

[vacunita]

Nothing. You use that exactly. You want to check what type of object you are getting. Either an [object NodeList] or a [object HTMLInputElement].

And leave the square brackets in place. The toString function call returns exactly those strings for each type. So that's what you want to check against.

----------------------------------
Phil AKA Vacunita
----------------------------------
Ignorance is not necessarily Bliss, case in point:
Unknown has caused an Unknown Error on Unknown and must be shutdown to prevent damage to Unknown.

Web & Tech

 

[mat41]

Hi there - it never enters the if or the elseif regardless of how many checkboxes are on the page. I have placed alerts there to identify this.

I have changed my original code to this which does work. Its probably a bit amateurish thought I would expect:

   if (document.getElementById('selectedDocs').checked)
   {
       //this is here to handle the situation where there is only one checkbox being displayed
   }
   else
   {
      var checked = false; 
	  var field = myForm.selectedDocs; 
	  for(var j = 0; j < field.length; j++)
	  { 
		 if(field[j].checked == true)
		 { 
			checked = true; 
			break; 
		 } 
	  } 
	  if(!checked)
	  { 
		 alert("You have not ticked any options.  At least one must be selected to proceed!") 
		 return false; 
	  }
   }