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I want to check if the first checkbox in a tr is selected not all the checkbox that is found in this tr.

For the time being i have this code :

var b = false;
$j('#tb1 td input:checkbox').each(function(){ 
      if($j(this).is(':checked')){
    b = true;
      }
});

this check if there is at least one checkbox check but if i add this to my selector :

$j('#tb1 td input:first:checkbox').each(function(){ 
      if($j(this).is(':checked')){
    b = true;
      }
});

it check for only the first row not for all the rows and only the first checkbox. How can i achieve this by using the "first" selector ? Thanks in advance

I want to check if the first checkbox in a tr is selected not all the checkbox that is found in this tr.

For the time being i have this code :

var b = false;
$j('#tb1 td input:checkbox').each(function(){ 
      if($j(this).is(':checked')){
    b = true;
      }
});

this check if there is at least one checkbox check but if i add this to my selector :

$j('#tb1 td input:first:checkbox').each(function(){ 
      if($j(this).is(':checked')){
    b = true;
      }
});

it check for only the first row not for all the rows and only the first checkbox. How can i achieve this by using the "first" selector ? Thanks in advance

• javascript
• jquery
• html
• checkbox

Share Improve this question Follow edited Sep 19, 2013 at 6:37 Harry 89.8k2626 gold badges212212 silver badges222222 bronze badges asked Sep 19, 2013 at 6:36 vanessenvanessen 1,26011 gold badge1414 silver badges1919 bronze badges 2

• can u create jsfiddle... – Somnath Kharat Commented Sep 19, 2013 at 6:40
• do you want to validate whether all the first checkboxes are checked or whether any one of them is checked – Arun P Johny Commented Sep 19, 2013 at 6:41

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4 Answers 4

Sorted by: Reset to default 14

Try

var b = false;
$j('#tb1 tr').find('input:checkbox:first').each(function(){ 
    if(this.checked){
        b = true;
    }
});

Your jquery code is wrong, you are using the correct selector but in wrong place..try this

$j('#tb1 td input:checkbox:first').

More infor about :First is here

Please try it

 var b = false;
  $j('#tb1 tr input:checkbox:first').each(function(){
    if(this.checked){
      b = true;
    }
  });

You are doing correct but placing of selector is wrong.

change

$j('#tb1 td input:first:checkbox').

to

$j('#tb1 td input:checkbox:first').

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