how to use index jquery each code example

Example 1: jquery each get index

$( "li" ).each(function( index ) {
  console.log( index + ": " + $( this ).text() );
});

Example 2: for each loop class jquery

$('.testimonial').each(function(i, obj) {
    //test
});

Example 3: foreach jquery

$( "li" ).each(function( index ) {
  console.log( index + ": " + $( this ).text() );
});