private static string EncodeField(string str) // 将字段值编码(含非ASCII码时)
{
string utf8Str = MyEncoder.EncodeWithUTF8(str);
string base64Str = MyEncoder.EncodeWithBase64(utf8Str);
string encodedFieldStr = String.Format("=?UTF-8?B?{0}?=", base64Str);
return(encodedFieldStr);
}
private static string BodyToStr(Body body) // 将信体转为字符串
{
string bodyStr = "";
// Content-Type
if (body.IsMulti)
{
bodyStr += String.Format("Content-Type: {0};\r\n\tboundary=\"{1}\"\r\n", GetContentTypeStr(body.ContentType), body.Boundary);
}
else if (body.IsAttachment)
{
bodyStr += String.Format("Content-Type: {0};\r\n\tname=\"{1}\"\r\n", GetContentTypeStr(body.ContentType), body.Name);
}
else
{
bodyStr += String.Format("Content-Type: {0};\r\n\tcharset=\"{1}\"\r\n", GetContentTypeStr(body.ContentType), "UTF-8");
}
// Content-Transfer-Encoding
if (!body.IsMulti)
{
bodyStr += String.Format("Content-Transfer-Encoding: base64\r\n");
}
// Other Attributes
if (body.IsAttachment)
{
bodyStr += String.Format("Content-Disposition: attachment; filename=\"{0}\"\r\n", body.Name);
}
/* 构建邮件体 */
if (body.IsMulti)
{
foreach (Body subBody in body.SubBodies)
{
bodyStr += String.Format("\r\n--{0}\r\n", body.Boundary); // 添加起头
bodyStr += BodyToStr(subBody);
}
bodyStr += String.Format("\r\n--{0}--\r\n", body.Boundary); // 添加结尾
}
else
{
string base64Data = MyEncoder.EncodeWithBase64(body.Data); // 编码为base64
string dstStr = "";
dstStr += "\r\n";
for (int i = 0; i < base64Data.Length; i += 75) // 保证每行不超过80字符
{
if (i + 75 < base64Data.Length)
{
dstStr += base64Data.Substring(i, 75) + "\r\n";
}
else
{
dstStr += base64Data.Substring(i, base64Data.Length - i) + "\r\n";
}
}
dstStr += "\r\n";
bodyStr += dstStr;
}
return(bodyStr);
}