这个控件里面其实包括了之前所有的控件,水平滚动,垂直滚动,列表框,这个组合框是拼凑起来的.想慢慢地,一步步摆脱系统控件,自己写控件其实也挺有意思的. -This controls which actually includes all of the controls before, horizontal scrolling, vertical scrolling list box, the combo box is pieced together. Think slowly, step by step to get rid of system control, write control is actually quite interesting.