设置Artist字段时Taglib数组异常

时间:2014-04-29 14:48:23

标签: c# taglib

我在这个编辑ID3数据的函数中使用Taglib.tag.Performers继续获取数组超出范围的异常。我在别处读到清除tag.performers []可以提供帮助(如果为null)但我有时仍然会收到错误。

错误讯息:

  

"索引超出了array.Data:

的范围      

' System.Collections.ListDictionaryInternal' for test.mp3"

var fileArr = Directory.GetFiles(BasePath, "*.*", SearchOption.AllDirectories).Where(s => s.EndsWith(".mp3") || s.EndsWith(".m4a")).ToArray();

foreach (var file in fileArr)
{
    string fileName = Path.GetFileName(file);
    string tagArtist = "";
    string tagTitle = "";
    string tempRegFilename = fileName;
    string title = "";

    //Apply to tag
    TagLib.File mp3tag = TagLib.File.Create(file);

    if (mp3tag.Tag.Title != null && mp3tag.Tag.Title.Length > 1)
    {
        title = mp3tag.Tag.Title;
    } 
    else
    {
        mp3tag.Tag.Title = String.Empty;
    }

    if (mp3tag.Tag.Performers[0].Length < 1 || mp3tag.Tag.Performers[0] == null)
    {
        mp3tag.Tag.Performers[0] = null;
        mp3tag.Tag.Performers = new[] { String.Empty };
        mp3tag.Save();
    }

    if (mp3tag.Tag.Performers[0].Length > 1)
    {
        string[] performers = mp3tag.Tag.Performers;
        if (title.Length > 2 && performers[0].Length > 1)
        {
            tagTitle = title;
            tagArtist = performers[0].ToString();
            Log.Info("ID3 Artist: " + "[" + tagArtist + "]");
            Log.Info("ID3 Title: " + "[" + tagTitle + "]");
            Log.Info("Tag data OK");
        }
    }
    //Get artist from filename
    if (mp3tag.Tag.Performers[0].Length < 1 || mp3tag.Tag.Performers == null)
    {
        mp3tag.Tag.Performers = new[] { String.Empty };
        string prevArtist = String.Empty;

        if (tempRegFilename.Contains("-"))
        {
            Log.Info("Artist data missing...");
            string[] words = tempRegFilename.Split('-');
            {
                words[0] = words[0].Trim();
                string perf = words[0];
                mp3tag.Tag.Performers = new[] { perf };
                Log.Info("Artists changed from \'" + prevArtist + "\' to " + "'" + perf + "'" + "\r\n");
                mp3tag.Save();
            }
        }
        mp3tag.Save();
    }
}

catch (Exception ex)
{
    Log.Error("TAG EXCEPTION: " + ex.Message + "Data: " + "'" + ex.Data + "'" + " for " + fileName + "\r\n" + ex.HelpLink);
}

任何人都能看出错误吗?我没有太多经验,可以使用帮助。感谢。

1 个答案:

答案 0 :(得分:2)

您似乎在许多地方假设mp3Tag.Tag.Performers中至少有一个元素。如果它没有,那么只要您尝试访问mp3tag.Tag.Performers[0]

,就会提到您提到的例外情况

看起来您可能正试图通过此代码来捕捉这种可能性:

if (mp3tag.Tag.Performers[0].Length < 1 || mp3tag.Tag.Performers[0] == null)
{
    mp3tag.Tag.Performers[0] = null;
    mp3tag.Tag.Performers = new[] { String.Empty };
    mp3tag.Save();
}

但是你的逻辑是不正确的:你从数组中获取第一个元素(显然是string)并检查长度,而不是检查数组的长度本身。试试这个:

if (mp3tag.Tag.Performers.Length < 1 || mp3tag.Tag.Performers[0] == null)
{
    mp3tag.Tag.Performers = new[] { String.Empty };
    mp3tag.Save();
}

PS:如果您的日志包含异常的堆栈跟踪,而不仅仅是其消息,那么您可以更轻松地查看错误所在。我通常发现最好只在异常本身上使用ToString()