Using official method

casper.then(function(){
  this.each(yourArr, function(self, element) {
    self.echo(element);
  });
});

Or using basic for statement

casper.then(function(){
  for(var i = 0; i < yourArr.length; i++){
    this.echo(yourArr[i]);
  }
});

However, javaScript method - forEach and jQuery method - $.each cannot work here! These two method will return null or stop scripting.