MinIO等设置上传的文件可预览

为什么浏览器对有些图片是直接预览打开，对有些图片是直接下载？—— 原由就在Content-Type响应头上；

Content-Type响应头的作用：

Content-Type 用于向接收方说明传输资源的媒体类型，从而让浏览器用指定码表去解码。

    DEFAULT("default","application/octet-stream"),
    JPG("jpg", "image/jpeg"),
    TIFF("tiff", "image/tiff"),
    GIF("gif", "image/gif"),
    JFIF("jfif", "image/jpeg"),
    PNG("png", "image/png"),
    TIF("tif", "image/tiff"),
    ICO("ico", "image/x-icon"),
    JPEG("jpeg", "image/jpeg"),
    WBMP("wbmp", "image/vnd.wap.wbmp"),
    FAX("fax", "image/fax"),
    NET("net", "image/pnetvue"),
    JPE("jpe", "image/jpeg"),
    RP("rp", "image/vnd.rn-realpix");