C application interface development foundation - form control (4) - selection control

Select class control

The selection class control has a drop-down combo box （ComboBox） Control 、 Check box （CheckBox） Control 、 Radio button （RadioButton） Control 、 Value selection （NumreicUpDown） Controls and lists （ListBox） Control .

1、 Drop down combo box control

The drop-down combo box control is called the drop-down combo box control , By System.Windows.Forms.ComboBox Class provides the , The main function is to display a set of data to the user in the form of combo box , When the user clicks, the following pull box will be displayed to the user for the user to select one from .

1、 Create a drop box and add content

2、 Check all the text of the editable part in the drop-down combo box

2、 Check box control

Check box control , Allows the user to select and clear association options . Unlike radio buttons , Check boxes, whether in the same container or in different containers , Multiple choices are allowed .

Judge the check box

Realization CheckBox Control

3、 Radio button controls

Radio button controls , When paired with other radio buttons , Allows the user to select a single option from a set of options . in other words , When there are more than two radio buttons in the same container , Only one can be selected . But several groups of radio buttons not in the same container are not associated with each other , There can be more than one selected .

Use RadioButton Control completes a choice question .

4、 Numeric selection control

Numerical selection control is also called numerical selection control , Is a control for displaying and entering values , Control provides a pair of up and down arrows , The main function is to increase or decrease a number by a certain value . It mainly has four common attributes ：

（1）Increment Property indicates the amount of increase or decrease each time the button is clicked .

（2）Maximum Attribute represents the maximum value .

（3）Minumum Attribute represents the minimum value .

（4）Value Property represents the current value .

5、 List control

List control is also called list box , It displays a list of items for the user to select . In the list box , Users can choose one at a time , You can also choose multiple .

1、 stay ListBox Control

2、 Select multiple items in the list box