I want to add a class to a li with specific Id. I tried this:

function updateIndex(indexValue){
    $('li[id=' + indexValue + ']').addClass("selectedQuestion")

}

I am not able to access indexValue variable in the li selector.

I want to add a class to a li with specific Id. I tried this:

function updateIndex(indexValue){
    $('li[id=' + indexValue + ']').addClass("selectedQuestion")

}

I am not able to access indexValue variable in the li selector.

• javascript
• jquery
• html
• css

3 Answers 3

You need to do a string concatenation to use the value of the indexValue parameter:

$('li[id=' + indexValue + ']').addClass("selectedQuestion")

Or, given the attribute you are selecting by is an id:

$('li#' + indexValue).addClass("selectedQuestion");

Or, given that id is supposed to be unique you shouldn't need the 'li' part (unless your meaning is to select that element only if it has that id and is an li element):

$('#' + indexValue).addClass("selectedQuestion");

function updateIndex(index){
   $('li[id=' + index +']').addClass("selectedQuestion")

}

Use this code instead of yours. You have to concatinate the indexValue variable

function updateIndex(indexValue){
  $('li[id=' + indexValue + ']').addClass("selectedQuestion")

}