我建议使用WebBrowser控件。

如果gif在网络上，你可以在XAML中设置源代码:

<WebBrowser Source="https://media.giphy.com/media/Ent2j55lyQipa/giphy.gif" />

如果它是一个本地文件，您可以从后台代码创建源代码。

XAML:

<WebBrowser x:Name="WebBrowser" />

后台代码:

private void Window_Loaded(object sender, RoutedEventArgs e)
{
    string curDir = Directory.GetCurrentDirectory();
    this.WebBrowser.Source = new Uri(String.Format("file:///{0}/10-monkey.gif", curDir));
}

我使用这个库:https://github.com/XamlAnimatedGif/WpfAnimatedGif

首先，将库安装到项目中(使用包管理器控制台):

    PM > Install-Package WpfAnimatedGif

然后，使用这个片段到XAML文件:

    <Window x:Class="WpfAnimatedGif.Demo.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:gif="http://wpfanimatedgif.codeplex.com"
        Title="MainWindow" Height="350" Width="525">
        <Grid>
            <Image gif:ImageBehavior.AnimatedSource="Images/animated.gif" />
        ...

希望能有所帮助。

来源:https://github.com/XamlAnimatedGif/WpfAnimatedGif

我无法让这个问题最流行的答案(上面由达里奥提出)正常工作。结果是奇怪的、起伏不定的动画和奇怪的工件。 目前为止我找到的最佳解决方案: https://github.com/XamlAnimatedGif/WpfAnimatedGif

你可以用NuGet安装它

WpfAnimatedGif安装包

并使用它，在一个新的名称空间的窗口，你想添加gif图像，并使用它如下所示

<Window x:Class="MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:gif="http://wpfanimatedgif.codeplex.com" <!-- THIS NAMESPACE -->
    Title="MainWindow" Height="350" Width="525">

<Grid>
    <!-- EXAMPLE USAGE BELOW -->
    <Image gif:ImageBehavior.AnimatedSource="Images/animated.gif" />

这个包非常简洁，你可以像下面这样设置一些属性

<Image gif:ImageBehavior.RepeatBehavior="3x"
       gif:ImageBehavior.AnimatedSource="Images/animated.gif" />

你也可以在你的代码中使用它:

var image = new BitmapImage();
image.BeginInit();
image.UriSource = new Uri(fileName);
image.EndInit();
ImageBehavior.SetAnimatedSource(img, image);

编辑:Silverlight支持

根据josh2112的评论，如果你想在Silverlight项目中添加GIF动画支持，请使用github.com/XamlAnimatedGif/XamlAnimatedGif

检查我的代码，我希望这对你有帮助:)

         public async Task GIF_Animation_Pro(string FileName,int speed,bool _Repeat)
                    {
    int ab=0;
                        var gif = GifBitmapDecoder.Create(new Uri(FileName), BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
                        var getFrames = gif.Frames;
                        BitmapFrame[] frames = getFrames.ToArray();
                        await Task.Run(() =>
                        {


                            while (ab < getFrames.Count())
                            {
                                Thread.Sleep(speed);
try
{
                                Dispatcher.Invoke(() =>
                                {
                                    gifImage.Source = frames[ab];
                                });
                                if (ab == getFrames.Count - 1&&_Repeat)
                                {
                                    ab = 0;

                                }
                                ab++;
            }
 catch
{
}

                            }
                        });
                    }

or

     public async Task GIF_Animation_Pro(Stream stream, int speed,bool _Repeat)
            {
 int ab = 0;   
                var gif = GifBitmapDecoder.Create(stream , BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
                var getFrames = gif.Frames;
                BitmapFrame[] frames = getFrames.ToArray();
                await Task.Run(() =>
                {


                    while (ab < getFrames.Count())
                    {
                        Thread.Sleep(speed);
    try
    {


                     Dispatcher.Invoke(() =>
                        {
                            gifImage.Source = frames[ab];
                        });
                        if (ab == getFrames.Count - 1&&_Repeat)
                        {
                            ab = 0;

                        }
                        ab++;
    }
     catch{} 



                    }
                });
            }

上面的方法我都试过了，但每个方法都有自己的不足，感谢大家，我想出了自己的GifImage:

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Windows.Controls;
    using System.Windows;
    using System.Windows.Media.Imaging;
    using System.IO;
    using System.Windows.Threading;

    namespace IEXM.Components
    {
    public class GifImage : Image
    {
            #region gif Source, such as "/IEXM;component/Images/Expression/f020.gif"
            public string GifSource
            {
                    get { return (string)GetValue(GifSourceProperty); }
                    set { SetValue(GifSourceProperty, value); }
            }

            public static readonly DependencyProperty GifSourceProperty =
                    DependencyProperty.Register("GifSource", typeof(string),
                    typeof(GifImage), new UIPropertyMetadata(null, GifSourcePropertyChanged));

            private static void GifSourcePropertyChanged(DependencyObject sender,
                    DependencyPropertyChangedEventArgs e)
            {
                    (sender as GifImage).Initialize();
            }
            #endregion

            #region control the animate
            /// <summary>
            /// Defines whether the animation starts on it's own
            /// </summary>
            public bool IsAutoStart
            {
                    get { return (bool)GetValue(AutoStartProperty); }
                    set { SetValue(AutoStartProperty, value); }
            }

            public static readonly DependencyProperty AutoStartProperty =
                    DependencyProperty.Register("IsAutoStart", typeof(bool),
                    typeof(GifImage), new UIPropertyMetadata(false, AutoStartPropertyChanged));

            private static void AutoStartPropertyChanged(DependencyObject sender,
                    DependencyPropertyChangedEventArgs e)
            {
                    if ((bool)e.NewValue)
                            (sender as GifImage).StartAnimation();
                    else
                            (sender as GifImage).StopAnimation();
            }
            #endregion

            private bool _isInitialized = false;
            private System.Drawing.Bitmap _bitmap;
            private BitmapSource _source;

            [System.Runtime.InteropServices.DllImport("gdi32.dll")]
            public static extern bool DeleteObject(IntPtr hObject);

            private BitmapSource GetSource()
            {
                    if (_bitmap == null)
                    {
                            _bitmap = new System.Drawing.Bitmap(Application.GetResourceStream(
                                     new Uri(GifSource, UriKind.RelativeOrAbsolute)).Stream);
                    }

                    IntPtr handle = IntPtr.Zero;
                    handle = _bitmap.GetHbitmap();

                    BitmapSource bs = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(
                            handle, IntPtr.Zero, Int32Rect.Empty, BitmapSizeOptions.FromEmptyOptions());
                    DeleteObject(handle);
                    return bs;
            }

            private void Initialize()
            {
            //        Console.WriteLine("Init: " + GifSource);
                    if (GifSource != null)
                            Source = GetSource();
                    _isInitialized = true;
            }

            private void FrameUpdatedCallback()
            {
                    System.Drawing.ImageAnimator.UpdateFrames();

                    if (_source != null)
                    {
                            _source.Freeze();
                    }

               _source = GetSource();

              //  Console.WriteLine("Working: " + GifSource);

                    Source = _source;
                    InvalidateVisual();
            }

            private void OnFrameChanged(object sender, EventArgs e)
            {
                    Dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action(FrameUpdatedCallback));
            }

            /// <summary>
            /// Starts the animation
            /// </summary>
            public void StartAnimation()
            {
                    if (!_isInitialized)
                            this.Initialize();


             //   Console.WriteLine("Start: " + GifSource);

                    System.Drawing.ImageAnimator.Animate(_bitmap, OnFrameChanged);
            }

            /// <summary>
            /// Stops the animation
            /// </summary>
            public void StopAnimation()
            {
                    _isInitialized = false;
                    if (_bitmap != null)
                    {
                            System.Drawing.ImageAnimator.StopAnimate(_bitmap, OnFrameChanged);
                            _bitmap.Dispose();
                            _bitmap = null;
                    }
                    _source = null;
                    Initialize();
                    GC.Collect();
                    GC.WaitForFullGCComplete();

             //   Console.WriteLine("Stop: " + GifSource);
            }

            public void Dispose()
            {
                    _isInitialized = false;
                    if (_bitmap != null)
                    {
                            System.Drawing.ImageAnimator.StopAnimate(_bitmap, OnFrameChanged);
                            _bitmap.Dispose();
                            _bitmap = null;
                    }
                    _source = null;
                    GC.Collect();
                    GC.WaitForFullGCComplete();
               // Console.WriteLine("Dispose: " + GifSource);
            }
    }
}

用法:

<localComponents:GifImage x:Name="gifImage" IsAutoStart="True" GifSource="{Binding Path=value}" />

因为它不会导致内存泄漏，它动画gif图像自己的时间线，你可以尝试一下。

它非常简单，如果你使用<MediaElement>:

<MediaElement  Height="113" HorizontalAlignment="Left" Margin="12,12,0,0" 
Name="mediaElement1" VerticalAlignment="Top" Width="198" Source="C:\Users\abc.gif"
LoadedBehavior="Play" Stretch="Fill" SpeedRatio="1" IsMuted="False" />