/// <summary>
/// 匹配文件格式是否属于扩展名
/// </summary>
/// <param name="ext">文件名或文件扩展名</param>
/// <param name="stream">文件流</param>
/// <param name="allowExts">允许的扩展名(.txt;.doc)</param>
/// <returns></returns>
public static bool IsFormat(string ext, Stream stream, string allowExts)
{
if (stream == null || ext.IsNullOrEmpty() == true)
{
return(false);
}
var extArray = allowExts.Matches(@"\.\w+").Select(item => item.ToLower()).ToArray();
if (extArray.Length == 0)
{
return(false);
}
var formatValue = ResFormat.ReadStreamFormatValue(stream);
if (formatValue == null)
{
return(false);
}
var format = new ResFormat(Path.GetExtension(ext).ToLower(), formatValue);
var formats = from k in ResFormat.KNOW_FORMAT_LIST
join e in extArray
on k.Extension equals e
select k;
return(formats.Any(f => f.Equals(format)));
}
/// <summary>
/// 流是否为指定的格式一种
/// </summary>
/// <param name="stream">流</param>
/// <param name="exts">格式</param>
/// <returns></returns>
public static bool IsInFormat(Stream stream, string exts)
{
if (stream == null)
{
return(false);
}
var extArray = exts.Matches(@"\.\w+").Select(item => item.ToLower()).ToArray();
if (extArray.Length == 0)
{
return(false);
}
var formats = from k in ResFormat.KNOW_FORMAT_LIST
join e in extArray
on k.Extension equals e
select k;
var formatValue = ResFormat.ReadStreamFormatValue(stream);
return(formats.Any(f => formatValue.SequenceEqual(f.FormatValue)));
}