When adding a new source at the end of the previous song finished, the plugin media element will report an error

Question

I want to realize that auto play next song when the previous song was finished playing,so I add a function for the event of mediaended, and add a new source by the mediaelemen object's properties source(mediaelement.source) ,however it report a bug, I can't find reason and resolve method

you can find all code by this link：

https://github.com/fsdfsfd/SimpleAudioPlayer

I'll give you a picture, and it'll show you exactly where the bug is：

The white highlighted areas in the picture mean:

When the onmediaended function calls loadsongomediaelementsource function meanwhile The program runs to mediaelemnt. source=, Bugs are starting to appear, but the value on the right side of the equal sign runs correctly

Answer 1

Hello,

When you add the song, your SongName will be null, you will get the null exceptions, I get the song name from Sony_path and set it like following code.

public void AddSong(string Song_path)
{
    Song song = new Song();
    song.InitInstanceByTagLib(Song_path);
 
    int index = Song_path.LastIndexOf('\\');
    if (index >= 0)
    {
        song.SongName = Song_path.Substring(index + 1);       
    }
    SongList.Add(song.SongName,song);
    PlayList.Add(song.SongName);
}

Then you have added an Action and wrap it by try/catch when you change the song, your application could run normally and this exception is disappeared.

try
{
    // 使用闭包捕获参数
    Action updateAction = () => UpdateMediaElementSource(path, songname);
 
    // 使用 Dispatcher 延迟设置 Source 属性
    Dispatcher.Dispatch(updateAction);
}
catch (COMException comEx)
{
    // 处理 COMException
    Console.WriteLine($"COMException caught: {comEx.Message}");
}
catch (Exception ex)
{
    // 处理其他异常
    Console.WriteLine($"Exception caught: {ex.Message}");
}

Best Regards,

Leon Lu

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