[PostProviderExtension]
public class HasImageErrorCheckerPostExtension : IPostProviderExtension
{
    public void BindEvents(PostProviderBase postProvider)
    {
        postProvider.Added += new PostChanged(postProvider_Added);
    }

    void postProvider_Added(Model.PostInfo post)
    {
        try
        {
            StackFrame[] stacks = new StackTrace().GetFrames();
            if (post.Content.IndexOf("IMG") > -1 && post.HasImage == false)
            {
                StringBuilder sb = new StringBuilder();
                sb.AppendLine("問(wèn)題出現(xiàn)");
                sb.AppendLine("stack is:");
                sb.Append(ToString(stacks));

                sb.Append("content=");
                sb.AppendLine(post.Content);

                sb.Append("HasImage=");
                sb.AppendLine(UserPostContentProcessor.HasImage(post.Content).ToString());

                sb.Append("createUserID=");
                sb.AppendLine(post.CreateUserID.ToString());
                sb.AppendLine(string.Format("LoginUser={0},Level={1}",PageBase.GetLoginUser().ID,PageBase.GetLoginUser().LevelNo));

                TextLogWriter.NamedInstance("\\log\\HasImageErrorCheckerPostExtension\\").Write(sb.ToString());
            }
        }
        catch (Exception ex)
        { 
            TextLogWriter.NamedInstance("\\log\\HasImageErrorCheckerPostExtension\\").Write(ex);
        }
    }

    private string ToString(StackFrame[] stacks)
    {
        string result = string.Empty;
        foreach (StackFrame stack in stacks)
        {
            result += string.Format("{0} {1} {2} {3}\r\n", stack.GetFileName(),
                stack.GetFileLineNumber(),
                stack.GetFileColumnNumber(),
                stack.GetMethod().ToString());
        }
        return result;
    }
}