检查您的 UrlEncode 方法是否真的将换行符转换为%0a".这是一个两行电子邮件正文的示例:

Check that your UrlEncode method really translates newlines into "%0a". Here's an example of a 2-line email body:

https://mail.google.com/mail/?view=cm&ui=2&tf=0&fs=1&to=WHOEVER%40COMPANY.COM&su=SUBJECTHERE&body=LINE1%0aLINE2