CheckBox 是一个允许用户从选项列表中进行单个或多个选择的控件。在 C# 中,System.Windows.Forms 命名空间中的 CheckBox 类用于处理复选框控件。它是 Windows 窗体的一部分,用于获取用户的输入。它还可用于从 true/false 或 yes/no 等选项中进行选择。
用户可以单击复选框来选择关联的项目,并可以再次单击它来取消选择该项目。它可以与图像或文本或两者一起使用。
我们可以通过两种不同的方式创建复选框:
我们可以在设计时创建复选框,方法是从工具箱中拖动复选框控件,然后将其放在 Windows 窗体上。然后,我们就可以进入复选框控件的属性并进行修改。
要在运行时创建复选框,我们需要使用 CheckBox 类。
语法:
CheckBox check_box = new CheckBox();
之后,我们就可以根据自己的需求设置复选框的属性了。
//setting location of checkbox check_box.Location = new Point(300,150); //setting height and width for checkbox check_box.Height = 50; check_box.Width = 50; //setting text for checkbox check_box.Text = “Yes”;
最后,我们需要使用以下方法将此复选框添加到 Windows 窗体:
this.Controls.Add(check_box);
C# 为复选框提供了许多属性。
Property | Description |
AllowDrop | It is used to get or set a value that determines whether the checkbox control can accept data that a user drags onto it. |
Appearance | It is used to get or set a value that determines the appearance of the checkbox control. |
AutoCheck | It is used to get or set a value that determines whether the values of the Checked or CheckState properties or the appearance of the checkbox are automatically changed when the checkbox is clicked. |
AutoSize | It is used to get or set a value that determines whether the checkbox control resizes based on its content. |
BackColor | It is used to get or set the background color of the checkbox control. |
BackGroundImage | It is used to get or set the background image displayed in the checkbox control. |
CanFocus | It is used to get a value that determines whether the checkbox control can receive focus. |
Checked | It is used to get or set a value that determines whether the checkbox control is in the checked state. |
CheckState | It is used to get or set the state of the checkbox. |
DefaultSize | It is used to get the default size of the checkbox control. |
Enabled | It is used to get or set a value that determines whether the checkbox control can respond to user interaction. |
Focused | It is used to get a value that determines whether the checkbox control has input focus. |
Font | It is used to get or set the font of text displayed by the checkbox control. |
ForeColor | It is used to get or set the foreground color of the checkbox control. |
Height | It is used to get or set the height of the checkbox control. |
Image | It is used to get or set the image which is displayed on the checkbox control. |
Location | It is used to get or set the coordinates of the upper left corner of the control relative to the upper left corner of its parent container. |
Margin | It is used to get or set the space between controls. |
Name | It is used to get or set the name of the checkbox control. |
Size | It is used to get or set the height and width of the checkbox control. |
Text | It is used to get or set the text associated with the checkbox control. |
ThreeState | It is used to get or set a value that determines whether the checkbox will allow three check states instead of two. |
Width | It is used to get or set the width of the checkbox control. |
Let us see some important events for the CheckBox provided by C#:
Event | Description |
CheckedChanged | This event occurs when the value of Checked property changes. |
CheckStateChanged | This event occurs when the value of CheckState property changes. |
Click | This event occurs when the checkbox is clicked. |
GotFocus | This event occurs when the checkbox receives focus. |
Leave | This event occurs when the input focus leaves the checkbox. |
LostFocus | This event occurs when the checkbox loses focus. |
MouseClick | This event occurs when the checkbox is clicked by the mouse. |
MouseDoubleClick | This event occurs when the checkbox is double-clicked by a mouse. |
TextChanged | This event occurs when the value of Text property changes. |
Below is an example of how to implement the checkbox in c #
Example:
Code:
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; namespace WindowsFormsApp1 { public partial class CheckBoxDemo : Form { public CheckBoxDemo() { InitializeComponent(); } private void CheckBoxDemo_Load(object sender, EventArgs e) { //Creating and setting properties of Label Label label = new Label(); label.Text = "Select your technical skills"; label.AutoSize = true; label.Location = new Point(192, 77); label.Font = new Font("Microsoft Sans Serif", 11); //Adding label to form this.Controls.Add(label); //Creating and setting properties of CheckBox CheckBox checkbox1 = new CheckBox(); checkbox1.Location = new Point(195, 111); checkbox1.Text = "C"; //Adding checkbox to form this.Controls.Add(checkbox1); CheckBox checkbox2 = new CheckBox(); checkbox2.Location = new Point(195, 156); checkbox2.Text = "C++"; this.Controls.Add(checkbox2); CheckBox checkbox3 = new CheckBox(); checkbox3.Location = new Point(195, 195); checkbox3.Text = "C#"; this.Controls.Add(checkbox3); CheckBox checkbox4 = new CheckBox(); checkbox4.Location = new Point(195, 235); checkbox4.Text = "JAVA"; this.Controls.Add(checkbox4); CheckBox checkbox5 = new CheckBox(); checkbox5.Location = new Point(195, 275); checkbox5.Text = "HTML"; this.Controls.Add(checkbox5); } } }
Output:
A checkbox in C# can also have an indeterminate state. This can be achieved by setting the CheckState property to ‘Indeterminate. It is a state between ‘Yes’ and ‘No’ in which the checkbox will neither be checked nor unchecked.
以上是C# 中的复选框的详细内容。更多信息请关注PHP中文网其他相关文章!