Control.Visible 属性

定义

获取或设置一个值,该值指示是否显示该控件及其所有子控件。Gets or sets a value indicating whether the control and all its child controls are displayed.

public:
 property bool Visible { bool get(); void set(bool value); };
public bool Visible { get; set; }
member this.Visible : bool with get, set
Public Property Visible As Boolean

属性值

如果显示该控件及其所有子控件,则为 true;否则为 falsetrue if the control and all its child controls are displayed; otherwise, false. 默认值为 trueThe default is true.

示例

下面的代码示例使用派生类 VScrollBarHScrollBar 并根据 PictureBox 控件中显示的 Image 大小设置其 Visible 属性值。The following code example uses the derived classes VScrollBar and HScrollBar and sets their Visible property values, based on the size of an Image being displayed in a PictureBox control. 此示例要求在窗体上创建了 PictureBox,并且已在 PictureBox上创建 HScrollBarVScrollBar 控件。This example requires that a PictureBox has been created on a form and that HScrollBar and VScrollBar controls have been created on the PictureBox. 当图像加载到图片框和窗体的 Resize 事件中时,应调用此代码。This code should be called when the image is loaded into the picture box and by the Resize event of the form.

public:
   void DisplayScrollBars()
   {
      // Display or hide the scroll bars based upon  
      // whether the image is larger than the PictureBox.
      if ( pictureBox1->Width > pictureBox1->Image->Width )
      {
         hScrollBar1->Visible = false;
      }
      else
      {
         hScrollBar1->Visible = true;
      }

      if ( pictureBox1->Height > pictureBox1->Image->Height )
      {
         vScrollBar1->Visible = false;
      }
      else
      {
         vScrollBar1->Visible = true;
      }
   }
public void DisplayScrollBars()
 {
    // Display or hide the scroll bars based upon  
    // whether the image is larger than the PictureBox.
    if (pictureBox1.Width > pictureBox1.Image.Width)
    {
       hScrollBar1.Visible = false;
    }
    else
    {
       hScrollBar1.Visible = true;
    }
    
    if (pictureBox1.Height > pictureBox1.Image.Height)
    {
       vScrollBar1.Visible = false;
    }
    else
    {
       vScrollBar1.Visible = true;
    }
 }
 
Public Sub DisplayScrollBars()
    ' Display or hide the scroll bars based upon  
    ' whether the image is larger than the PictureBox.
    If pictureBox1.Width > pictureBox1.Image.Width Then
        hScrollBar1.Visible = False
    Else
        hScrollBar1.Visible = True
    End If
    
    If pictureBox1.Height > pictureBox1.Image.Height Then
        vScrollBar1.Visible = False
    Else
        vScrollBar1.Visible = True
    End If
End Sub

注解

请注意,即使 Visible 设置为 true,如果用户在其他控件的后面都不可见,则该控件可能对用户不可见。Note that even if Visible is set to true, the control might not be visible to the user if it is obscured behind other controls.

适用于

另请参阅