这是一篇老文章,但我认为以下是更好的方法:
我认为您不应该使用布尔值来检查鼠标是否拖动当前控件。此外,使用PreviewMouse....
无法解决获取鼠标位置的问题(当鼠标不在控件上方时)。
您应该捕获鼠标。当您捕获了鼠标后,即使鼠标不在控件上方(甚至当鼠标离开当前窗口时),鼠标移动事件仍然会被触发。我认为这是正确的方法。它更简单易读。
以下是代码:
public partial class VisualBlock : UserControl
{
private Point _positionInBlock;
public VisualBlock()
{
InitializeComponent();
}
private void UserControl_MouseDown(object sender, MouseButtonEventArgs e)
{
_positionInBlock = Mouse.GetPosition(this);
this.CaptureMouse();
}
private void UserControl_MouseMove(object sender, MouseEventArgs e)
{
if (this.IsMouseCaptured)
{
var container = VisualTreeHelper.GetParent(this) as UIElement;
if(container == null)
return;
var mousePosition = e.GetPosition(container);
this.RenderTransform = new TranslateTransform(mousePosition.X - _positionInBlock.X, mousePosition.Y - _positionInBlock.Y);
}
}
private void UserControl_MouseUp(object sender, MouseButtonEventArgs e)
{
this.ReleaseMouseCapture();
}
}
更新:
如果你有一个窗口,比如一个画布,你可以将这些用户控件添加到画布中。
以下是它的要点:
WPF移动控件。
<Window x:Class="WPFTestControlMoveMouse.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WPFTestControlMoveMouse"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="30" />
<RowDefinition />
</Grid.RowDefinitions>
<Button Grid.Row="0" Click="Button_Click">New</Button>
<Canvas x:Name="MyCanvas" Grid.Row="1"></Canvas>
</Grid>
</Window>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace WPFTestControlMoveMouse
{
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void Button_Click(object sender, RoutedEventArgs e)
{
MyCanvas.Children.Add(new VisualBlock());
}
}
}
<UserControl x:Class="WPFTestControlMoveMouse.VisualBlock"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:WPFTestControlMoveMouse"
mc:Ignorable="d"
Width="300" Height="200" MouseDown="UserControl_MouseDown" MouseUp="UserControl_MouseUp" MouseMove="UserControl_MouseMove">
<Grid>
<Border BorderBrush="Black" BorderThickness="1" Background="Silver" />
<TextBlock FontSize="48" HorizontalAlignment="Center" VerticalAlignment="Center">Hi there!!</TextBlock>
</Grid>
</UserControl>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace WPFTestControlMoveMouse
{
public partial class VisualBlock : UserControl
{
private Point _positionInBlock;
public VisualBlock()
{
InitializeComponent();
}
private void UserControl_MouseDown(object sender, MouseButtonEventArgs e)
{
_positionInBlock = Mouse.GetPosition(this);
this.CaptureMouse();
}
private void UserControl_MouseMove(object sender, MouseEventArgs e)
{
if (this.IsMouseCaptured)
{
var container = VisualTreeHelper.GetParent(this) as UIElement;
var mousePosition = e.GetPosition(container);
this.RenderTransform = new TranslateTransform(mousePosition.X - _positionInBlock.X, mousePosition.Y - _positionInBlock.Y);
}
}
private void UserControl_MouseUp(object sender, MouseButtonEventArgs e)
{
this.ReleaseMouseCapture();
}
}
}
通过从标签控件派生来使用鼠标移动标签:
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Media;
namespace WPFTestControlMoveMouse
{
public class MyLabel : Label
{
private Point _positionInBlock;
protected override void OnMouseDown(MouseButtonEventArgs e)
{
_positionInBlock = Mouse.GetPosition(this);
this.CaptureMouse();
}
protected override void OnMouseMove(MouseEventArgs e)
{
if (this.IsMouseCaptured)
{
var container = VisualTreeHelper.GetParent(this) as UIElement;
var mousePosition = e.GetPosition(container);
this.RenderTransform = new TranslateTransform(mousePosition.X - _positionInBlock.X, mousePosition.Y - _positionInBlock.Y);
}
}
protected override void OnMouseUp(MouseButtonEventArgs e)
{
this.ReleaseMouseCapture();
}
}
}