Questions about output after character transcoding

Question about output after character transcoding header (& quot; content-Type: text/plain; charset = gb2312 & quot;); header (& quot; Content-Disposition: attachment; filename = & quot ;. date (& quot; YmdHis & quot; about output after character transcoding
Header ("content-Type: text/plain; charset = gb2312 ");
Header ("Content-Disposition: attachment; filename =". date ("YmdHis"). "test.xls ");
Echo iconv ("utf8", "gb2312", "Weibo ID \ t ");

Why is there no data in the exported excel table?

Rewrite utf8 in The iconv function to UTF-8.

Please explain the reason. thank you.

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Utf8 is UTF-8 encoded in mysql. UTF-8 is used in php.
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Discussion

Reference:

Positive solution on the first floor


But there is no problem in testing on another machine (ubantu), and there is a problem on my machine (win7.