<Window.Resources>
<local:ImageUrlConverter x:Key="imgConverter"/>
</Window.Resources>
<Image Source="{Binding ImgUrl,Converter={StaticResource imgConverter}}"
RenderOptions.BitmapScalingMode="HighQuality"/>
public class ImageUrlConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
string url = value?.ToString();
if (!string.IsNullOrWhiteSpace(url))
{
WebClient client = new WebClient();
var imgBytes = client.DownloadData(url);
if (imgBytes != null && imgBytes.Any())
{
MemoryStream ms = new MemoryStream(imgBytes);
ms.Seek(0, SeekOrigin.Begin);
BitmapImage bmi = new BitmapImage();
bmi.BeginInit();
bmi.StreamSource = ms;
bmi.EndInit();
if (bmi.CanFreeze)
{
bmi.Freeze();
}
return bmi;
}
}
return null;
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
}
![]()
//xaml
<Window x:Class="WpfApp1.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:behavior="http://schemas.microsoft.com/xaml/behaviors"
xmlns:local="clr-namespace:WpfApp1"
mc:Ignorable="d"
WindowState="Maximized"
WindowStyle="None"
Title="MainWindow" Height="450" Width="800">
<Window.DataContext>
<local:MainVM/>
</Window.DataContext>
<Window.Resources>
<local:ImageUrlConverter x:Key="imgConverter"/>
</Window.Resources>
<behavior:Interaction.Triggers>
<behavior:EventTrigger EventName="MouseDown">
<behavior:InvokeCommandAction
Command="{Binding MouseDownCommand}"
CommandParameter="{Binding RelativeSource={RelativeSource Mode=FindAncestor,AncestorType={x:Type Window}}}"/>
</behavior:EventTrigger>
</behavior:Interaction.Triggers>
<Grid>
<Image Source="{Binding ImgUrl,Converter={StaticResource imgConverter}}"
RenderOptions.BitmapScalingMode="HighQuality"/>
</Grid>
</Window>
//cs
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Net;
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 WpfApp1
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
}
public class MainVM : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
public string ImgUrl { get; set; } = "https://wx4.sinaimg.cn/mw690/007ucPXmgy1hteb8tr7gjj311x1kwhdt.jpg";
public DelCmd MouseDownCommand { get; set; }
public MainVM()
{
InitCommands();
}
private void InitCommands()
{
MouseDownCommand = new DelCmd(MouseDownCommandExecuted);
}
private void MouseDownCommandExecuted(object obj)
{
var win = obj as Window;
if (win != null)
{
var pt = Mouse.GetPosition(win);
MessageBox.Show($"X:{pt.X}\nY:{pt.Y}", "Location", MessageBoxButton.OK);
}
}
private void OnPropertyChanged(string propertyName)
{
var handler = PropertyChanged;
if (handler != null)
{
handler?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
}
public class ImageUrlConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
string url = value?.ToString();
if (!string.IsNullOrWhiteSpace(url))
{
WebClient client = new WebClient();
var imgBytes = client.DownloadData(url);
if (imgBytes != null && imgBytes.Any())
{
MemoryStream ms = new MemoryStream(imgBytes);
ms.Seek(0, SeekOrigin.Begin);
BitmapImage bmi = new BitmapImage();
bmi.BeginInit();
bmi.StreamSource = ms;
bmi.EndInit();
if (bmi.CanFreeze)
{
bmi.Freeze();
}
return bmi;
}
}
return null;
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
}
public class DelCmd : ICommand
{
public event EventHandler CanExecuteChanged
{
add
{
CommandManager.RequerySuggested += value;
}
remove
{
CommandManager.RequerySuggested -= value;
}
}
private Action<object> execute;
private Predicate<object> canExecute;
public DelCmd(Action<object> executeValue, Predicate<object> canExecuteValue)
{
this.execute = executeValue;
this.canExecute = canExecuteValue;
}
public DelCmd(Action<object> executeValue) : this(executeValue, null)
{
}
public bool CanExecute(object parameter)
{
if (canExecute == null)
{
return true;
}
return canExecute(parameter);
}
public void Execute(object parameter)
{
execute(parameter);
}
}
}