var comment = activeSheet.comments.add(5, 5, "Comment1");
comment.backColor("yellow");
comment.foreColor("green");
comment.displayMode(GC.Spread.Sheets.Comments.DisplayMode.hoverShown);
var comment1 = activeSheet.comments.add(1, 1, "");
comment1.text("Comment2");
comment1.displayMode(GC.Spread.Sheets.Comments.DisplayMode.alwaysShown);
comment1.backColor("red");
comment1.foreColor("blue");
var gcomments = activeSheet.comments.all();
for (var i = 0; i < gcomments.length; i++) {
alert(gcomments[i].text());
}