以下是我给出的代码以及我在邮件中收到的excel附件已损坏
#!/usr/bin/ksh
export MAILFROM="el@defiant.com"
export MAILTO="youremail@gmail.com"
export SUBJECT="Test PDF for Email"
export BODY="/home/el/email_body.htm"
export ATTACH="/home/el/pdf-test.pdf"
export ATTACH1="/home/el/excel-test.xls"
export MAILPART=`uuidgen` ## Generates Unique ID
export MAILPART_BODY=`uuidgen` ## Generates Unique ID
(
echo "From: $MAILFROM"
echo "To: $MAILTO"
echo "Subject: $SUBJECT"
echo "MIME-Version: 1.0"
echo "Content-Type: multipart/mixed; boundary=\"$MAILPART\""
echo ""
echo "--$MAILPART"
echo "Content-Type: multipart/alternative; boundary=\"$MAILPART_BODY\""
echo ""
echo "--$MAILPART_BODY"
echo "Content-Type: text/plain; charset=ISO-8859-1"
echo "You need to enable HTML option for email"
echo "--$MAILPART_BODY"
echo "Content-Type: text/html; charset=ISO-8859-1"
echo "Content-Disposition: inline"
cat $BODY
echo "--$MAILPART_BODY--"
echo "--$MAILPART"
echo 'Content-Type: application/pdf; name="'$(basename $ATTACH)'"'
echo "Content-Transfer-Encoding: uuencode"
echo 'Content-Disposition: attachment; filename="'$(basename $ATTACH)'"'
echo ""
echo "--$MAILPART"
echo 'Content-Type: application/msexcel; name="'$(basename $ATTACH1)'"'
echo "Content-Transfer-Encoding: Base-64"
echo 'Content-Disposition: attachment; filename="'$(basename $ATTACH1)'"'
echo ""
uuencode $ATTACH $(basename $ATTACH) && uuencode $ATTACH1 $(basename $ATTACH1)
echo "--$MAILPART--"
) | /usr/sbin/sendmail $MAILTO
请指导我关于excel的内容类型和内容编码类型，因为一旦我收到邮件文件，数据就会损坏。