JAVA--contenttype文件ajax_请求头常用的ContentType、文件上传

    public static String getcontentType(String FilenameExtension) {
        if (FilenameExtension.equalsIgnoreCase(".bmp")) {
            return "image/bmp";
        }
        if (FilenameExtension.equalsIgnoreCase(".gif")) {
            return "image/gif";
        }
        if (FilenameExtension.equalsIgnoreCase(".jpeg") ||
                FilenameExtension.equalsIgnoreCase(".jpg") ||
                FilenameExtension.equalsIgnoreCase(".png")) {
            return "image/jpg";
        }
        if (FilenameExtension.equalsIgnoreCase(".html")) {
            return "text/html";
        }
        if (FilenameExtension.equalsIgnoreCase(".txt")) {
            return "text/plain";
        }
        if (FilenameExtension.equalsIgnoreCase(".vsd")) {
            return "application/vnd.visio";
        }
        if (FilenameExtension.equalsIgnoreCase(".pptx") ||
                FilenameExtension.equalsIgnoreCase(".ppt")) {
            return "application/vnd.ms-powerpoint";
        }
        if (FilenameExtension.equalsIgnoreCase(".docx") ||
                FilenameExtension.equalsIgnoreCase(".doc")) {
            return "application/msword";
        }
        if (FilenameExtension.equalsIgnoreCase(".xml")) {
            return "text/xml";
        }
        if (FilenameExtension.equalsIgnoreCase(".xlsx")) {
            return "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
        }

        if (FilenameExtension.equalsIgnoreCase(".mp4")) {
            return "audio/mp4,video/mp4";
        }
        if (FilenameExtension.equalsIgnoreCase(".xls")) {
            return "application/vnd.ms-excel";
        }

        if (FilenameExtension.equalsIgnoreCase(".zip")) {
            return "application/zip";
        }



        return "image/jpg";
    }