This control is similar to the IP entry box displayed in some of Microsoft's networking dialogs. It contains space for each part of a dotted quad IP address and rejects invalid entries.
来源: http://www.freevbcode.com/ShowCode.Asp?ID=368
这个控件与显示于一些Microsoft网络对话框中的IP输入框相似。它为每一个dotted quad IP地址的每一部分保留空隙,拒绝错误的输入。