如何编制纯asp程序读写图形文件的尺寸大小

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'::: :::
'::: This routine will attempt to identify any filespec passed :::
'::: as a graphic file (regardless of the extension). This will :::
'::: work with BMP, GIF, JPG and PNG files. :::
'::: :::
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'::: Based on ideas presented by David Crowell :::
'::: (credit where due) :::
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'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
'::: blah blah Copyright *c* MM, Mike Shaffer blah blah :::
'::: blah blah ALL RIGHTS RESERVED WORLDWIDE blah blah :::
'::: blah blah Permission is granted to use this code blah blah :::
'::: blah blah in your projects, as long as this blah blah :::
'::: blah blah copyright notice is included blah blah :::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
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'::: :::
'::: This function gets a specified number of bytes from any :::
'::: file, starting at the offset (base 1) :::
'::: :::
'::: Passed: :::
'::: flnm => Filespec of file to read :::
'::: offset => Offset at which to start reading :::
'::: bytes => How many bytes to read :::
'::: :::
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function GetBytes(flnm, offset, bytes)
Dim objFSO
Dim objFTemp
Dim objTextStream
Dim lngSize