列出所有最近使用的工作簿

private void button1_Click(object sender, EventArgs e)
{
    StringBuilder sb = new StringBuilder();
    for (int i = 1; i < this.Application.RecentFiles.Count; i++)
    {
        sb.Append(this.Application.RecentFiles[i].Name);
        sb.Append("\n");
    }
    MessageBox.Show(sb.ToString(),"All RecentFiles");
}