How Can JavaScript Style Specific Lines of Text Like CSS\'s `:first-line` but for Any Line?

Selecting Specific Text Lines with JavaScript

How can we style specific lines of text, similar to the :first-line CSS pseudo-element, without limiting it to just the first line?

While CSS alone is insufficient for this task, JavaScript offers a solution.

JavaScript Implementation:

We can wrap each word in a span element using JavaScript:

$(function(){ 
  var p = $('p'); 
  var words = p.text().split(' '); 
  var text = ''; 
  $.each(words, function(i, w){
                   if($.trim(w)) text = text + '<span>' + w + '</span> ' }
        ); //each word 
  p.html(text); 

To determine the line number for each span, we use the Window's resize event to calculate the vertical position of each span:

  $(window).resize(function(){ 

    var line = 0; 
    var prevTop = -15; 
    $('span', p).each(function(){ 
      var word = $(this); 
      var top = word.offset().top; 
      if(top!=prevTop){ 
        prevTop=top; 
        line++; 
      } 
      word.attr('class', 'line' + line); 
    });//each 

  });//resize 

Highlighting Even/Odd Rows:

For highlighting even/odd rows, the code can be simplified to:

  $(window).resize(function(){ 

    $('span', p).each(function(){ 
      var word = $(this); 
      var top = word.offset().top; 
      var line = Math.floor(top / 20);
      word.attr('class', (line % 2 == 0 ? 'even' : 'odd'));
    });//each
  });//resize 

Considerations:

This method assumes that words do not wrap within the same line, and changes in the class may affect the size or width of the words.

Example:

[Click here](https://jsbin.com/piwizateni/1/edit?html,css,js,output) for a working demonstration.

The above is the detailed content of How Can JavaScript Style Specific Lines of Text Like CSS's `:first-line` but for Any Line?. For more information, please follow other related articles on the PHP Chinese website!