How to change the number of rows in the textarea using jQuery

Question

I have a textarea with 5 lines. I want to show only one line and on focus it should show remaining 4 lines.

Answer 1

jQuery(function($){
  $('#foo').focus(function(){
    $(this).attr('rows',5);
  }).blur(function(){
    $(this).attr('rows',1);
  });
});

Or, using less jQuery, less typing, and getting a hair more performance:

jQuery(function($){
  $('#foo')
    .focus(function(){ this.rows=5 })
    .blur( function(){ this.rows=1 });
});