base64 常用的前缀

.doc——data:application/msword;base64,

.docx——data:application/vnd.openxmlformats-officedocument.wordprocessingml.document;base64,

.xls——data:application/vnd.ms-excel;base64,

.xlsx——data:application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;base64,

.pdf——data:application/pdf;base64,

.ppt——data:application/vnd.ms-powerpoint;base64,

.pptx——data:application/vnd.openxmlformats-officedocument.presentationml.presentation;base64,

.txt——data:text/plain;base64,

.png——data:image/png;base64,

.jpg——data:image/jpeg;base64,

.gif——data:image/gif;base64,

.svg——data:image/svg+xml;base64,

.ico——data:image/x-icon;base64,

.bmp——data:image/bmp;base64,