在用C#编写Windows程序时经常使用ComboBox控件，但此控件列表项只有text属性，与HTML中SELECT控件很不一样，使用很不方便，此代码就可以为ComboBox控件添加value属性！-With C# Preparation Windows programs often use ComboBox controls, but this controls only the list item text attributes, and HTML controls are very different in SELECT, the use of very inconvenient, this code can add the value attribute ComboBox control!