该代码并非原创,是在luocong的基础上进行了修改并添加了发送html的功能.功能:对需要或不需要认证的smtp服务器发送文字,html源码,和发送附件的功能.该代码具有良好的阅读性.-The code is not the original, luocong is on the basis of the revised and added this html function. function : need or require authentication smtp server to