备忘录
创建类/接口：（例如）ZCL_SEND_ATTACH
创建方法：SEND_PDF_FILE
参数：（具体各个用法这里不做详述）
IM_FILE_HEADER_TEXT
IM_EMAIL_SUBJECT_LINE
IM_EMAIL_BODY_TEXT
IM_EMAIL_ADDRESS
IM_EMAIL_DIST_NAME
IM_EMAIL_DIST_ID
IM_ATTACHMENT_NAME
IM_FILE_DELIMETER
IM_ITAB_1
IM_ITAB_2
IM_EMAIL_DO_NOT
IM_LAYOUT
EX_SEND_TO_ALL
EX_PDF_TABLE
实现代码：
Method send_pdf_file.
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