给定文本文件的前N个字节，如何确定这些字节是否为XML？

Question

给定byte[] peek，其中peek为N字节来自文本文件，如何确定peek是否为XML？

仅仅检查字符串开头的<是否足够？

Answer 1

要确定，给定字符串是否具有XML格式，您需要一个解析器（对于Java，请阅读this）。这是获得确切答案的唯一方法。

检查前几个字节，以便查找<?xml只能给出假设，无论它是否是有效的XML。但是，在你将其解析到最后之前，你不能完全确定。

Answer 2

According to the XML standard, your files should use <?xml to make it possible to tell if they are XML. If you have chosen not to follow that recommendation, there is no reliable way to tell. Some non-XML files will pass any test (by starting with <) that looks at small-N bytes. Others won't. Also note that a valid XML file may begin with a Unicode BOM character, so be sure to take that into account if you are going to go ahead and try this.