ITransformProvider.Move(Double, Double) Method

Definition

Moves the control.

public void Move (double x, double y);

Parameters

x
Double

Absolute screen coordinates of the left side of the control.

y
Double

Absolute screen coordinates of the top of the control.

Exceptions

If the CanMove property is false.

Examples

The following example shows one possible implementation of this method for a custom control that can be moved.

/// <summary>
/// Moves the provider to the specified position.
/// </summary>
/// <param name="x">The specified X screen coordinate.</param>
/// <param name="y">The specified Y screen coordinate</param>
void ITransformProvider.Move(double x, double y)
{
    int leftInt = (int)x;
    int topInt = (int)y;

    if (!((ITransformProvider)this).CanMove)
        throw new InvalidOperationException(
            "Operation cannot be performed.");

    // Move should never be allowed to place a control outside the 
    // bounds of its container; the control should always be accessible 
    // using the keyboard or mouse.
    // Use the bounds of the parent window to limit the placement 
    // of the custom control.
    int maxLeft = 10;
    int maxTop = 10;
    int maxRight =
        this.customControl.formWidth - this.customControl.Width - 10;
    int maxBottom =
        this.customControl.formHeight - this.customControl.Height - 10;

    if (leftInt < maxLeft)
        leftInt = 0;
    if (topInt < maxTop)
        topInt = 0;
    if (leftInt > maxRight)
        leftInt = maxRight;
    if (topInt > maxBottom)
        topInt = maxBottom;

    // Invoke control method on separate thread to avoid clashing with UI.
    // Use anonymous method for simplicity.
    this.customControl.Invoke(new MethodInvoker(delegate ()
    {
        this.customControl.Left = leftInt;
        this.customControl.Top = topInt;
    }));
}

Remarks

An object cannot be moved, resized, or rotated such that its resulting screen location would be completely outside the coordinates of its container and inaccessible to keyboard or mouse. For example, when a top-level window is moved completely off-screen or a child object is moved outside the boundaries of the container's viewport. In these cases the object is placed as close to the requested screen coordinates as possible with the top or left coordinates overridden to be within the container boundaries.

Applies to

產品 版本
.NET Framework 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
Windows Desktop 3.0, 3.1, 5, 6, 7, 8, 9

See also