摘要：
anel controls are most often used as—and are intended as—containers for other controls. They're often useful when you want to show or hide a group of controls at once, or when you want to add controls to a Web page in code. The figure below show four panels top, left, bottom and right 阅读全文
摘要：
The NumericUpDown control looks like a combination of a text box and a pair of arrows that the user can click to adjust a value. The control displays and sets a single numeric value from a list of choices. The user can increase and decrease the number by clicking up and down buttons, by pressing the UP and DOWN ARROW keys, or by typing a number. Clicking the UP ARROW key moves the value toward its maximum; clicking the DOWN ARROW key moves the position toward the minimum 阅读全文