問題描述

我剛剛開始使用 WPF.但我正在嘗試添加我的代碼(來自 Winforms)，使用戶能夠在運行時將任何控件拖動到他們希望的任何位置.但我似乎無法獲得鼠標的當前位置......嗯?鼠標沒有位置?:(

I've just started using WPF. But I'm trying to add my code that (from Winforms) enables the user to drag any control whereever they wish at runtime. But I can't seem to get the current Location of the mouse... Eh? There is no Location for Mouse? :(

推薦答案

在鼠標事件中可以使用 e.GetPosition 獲取當前鼠標位置.此函數可以提供相對于特定元素的鼠標位置，或者您可以只傳遞 null.

In the Mouse event you can use e.GetPosition to get the current mouse position. This function can provide the mouse position relative to a specific element or you can just pass null.

這是一個非常簡單的例子，沒有命中測試或任何東西，只是一個可以拖動的按鈕.我使用了一個畫布來保持它的簡短，但您可能會更好地使用轉換并將控件轉換到所需的位置.

Here is a very simple example, no hit testing or anything, just a button that you can drag around. And I used a canvas to keep it short, but you would probably do better to use a transform and translate the control to the desired position.

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
    <Canvas PreviewMouseLeftButtonDown="Canvas_PreviewMouseLeftButtonDown" 
            PreviewMouseMove="Canvas_PreviewMouseMove" 
            PreviewMouseLeftButtonUp="Canvas_PreviewMouseLeftButtonUp">
        <Button Name="dragButton" Width="80" Height="21" Canvas.Left="50" Canvas.Top="10">Drag Me!</Button>
    </Canvas>
</Window>

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;

namespace WpfApplication1
{
  public partial class MainWindow : Window
  {
    public MainWindow()
    {
      InitializeComponent();      
    }    

    private Point _startPoint;
    private bool _dragging = false;

    private void Canvas_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {         
      if (dragButton.CaptureMouse())
      {        
        _startPoint = e.GetPosition(null);
        _dragging = true;        
      }
    }

    private void Canvas_PreviewMouseMove(object sender, MouseEventArgs e)
    {
      if (_dragging)
      {        
        Point newPoint = e.GetPosition(null);
        double dx = newPoint.X - _startPoint.X;
        double dy = newPoint.Y - _startPoint.Y;

        Canvas.SetLeft(dragButton, Canvas.GetLeft(dragButton) + dx);
        Canvas.SetTop(dragButton, Canvas.GetTop(dragButton) + dy);
        _startPoint = newPoint;
      }
    }

    private void Canvas_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
      if (_dragging)
      {        
        _dragging = false;
        dragButton.ReleaseMouseCapture();
      }
    }    
  }
}

這篇關于運行時在窗體上拖動控件的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！