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覆巢之下焉有完卵。出来道上混,迟早是要还的。

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如何判断一个文件是不是jpg文件

2011-04-25 06:07:51| 分类： VC++ | 标签： |举报 |字号大中小订阅

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判断他的前几个字节是什么
bmp: "BM"
jpg: 0xFF, 0xDB
gif: "GIF"

通过二进制流的方式去读取

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