Binary() limit bit number?

[flashlab]

I wanna to download a jpg file via winhttp. First I receive the binary data as string. Just like '0xFFD8FFE000104A...'. Then write it to file like↓

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#include <WinHttp.au3>

Local $jpg = _load('img3.douban.com','/lpic/s3292023.jpg',2)
$jptg = StringMid($jpg,1,16386)
$temp_JPG=FileOpen(@ScriptDir&'\img\s3292023.jpg',26)
;~ MsgBox(0,BinaryLen(Binary($jptg))&' '&BinaryMid(Binary($jptg),1,2),IsBinary(Binary($jptg)))
FileWrite($temp_JPG,Binary($jptg))
FileClose($temp_JPG)

$jptg2 = StringMid($jpg,1,16388)
$temp_JPG=FileOpen(@ScriptDir&'\img\s3292024.jpg',26)
;~ MsgBox(0,BinaryLen(Binary($jptg2))&' '&BinaryMid(Binary($jptg2),1,2),IsBinary(Binary($jptg2)))
FileWrite($temp_JPG,Binary($jptg2))
FileClose($temp_JPG)

Func _load($hos,$req, $fo, $agent='',$fl='GET',$adata='')
    Local $hOpen, $hConnect, $hRequest, $sReturned
    If $agent='' Then
        $hOpen = _WinHttpOpen()
    Else
        $hOpen = _WinHttpOpen($agent)
    EndIf
    $hConnect = _WinHttpConnect($hOpen, $hos)
    $hRequest = _WinHttpOpenRequest($hConnect, $fl, $req)
   _WinHttpSendRequest($hRequest,'',$adata)
   _WinHttpReceiveResponse($hRequest)

   If _WinHttpQueryDataAvailable($hRequest) Then ; if there is data
    Do
        $sReturned &= _WinHttpReadData($hRequest,$fo)
    Until @error
   EndIf
   _WinHttpCloseHandle($hRequest)
   _WinHttpCloseHandle($hConnect)
   _WinHttpCloseHandle($hOpen)   
   Return $sReturned
EndFunc

the strange thing is ,when I pick up 8192 bytes, it can't normal save, else it will save as string...

Is Binary() has this number limitation?

Edited February 24, 2011 by flashlab

[jchd]

You seem to be mixing several points here.

What does _httpload() return?

StringMid will always return a *string*

BinaryMid will work on a binary variant and return a Binary variant.

bits are not bytes.

O yes, BTW, as explained in the help file, Language Reference > Datatypes § Binary you have that "Binary data, can contain up to 2147483647 bytes"

That should make any .JPG fit in a binary variant.

Edited February 23, 2011 by jchd

[flashlab]

You seem to be mixing several points here.

What does _httpload() return?

StringMid will always return a *string*

BinaryMid will work on a binary variant and return a Binary variant.

bits are not bytes.

O yes, BTW, as explained in the help file, Language Reference > Datatypes § Binary you have that "Binary data, can contain up to 2147483647 bytes"

That should make any .JPG fit in a binary variant.

Sorry for my poor English I've update the code. It now can be debuged directly. you will understand what I mean~

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#include <WinHttp.au3>

Local $jpg = _load('img3.douban.com','/lpic/s3292023.jpg',2)
$jptg = StringMid($jpg,1,16386)
$temp_JPG=FileOpen(@ScriptDir&'\img\s3292023.jpg',26)
;~ MsgBox(0,BinaryLen(Binary($jptg))&' '&BinaryMid(Binary($jptg),1,2),IsBinary(Binary($jptg)))
FileWrite($temp_JPG,Binary($jptg))
FileClose($temp_JPG)

$jptg2 = StringMid($jpg,1,16388)
$temp_JPG=FileOpen(@ScriptDir&'\img\s3292024.jpg',26)
;~ MsgBox(0,BinaryLen(Binary($jptg2))&' '&BinaryMid(Binary($jptg2),1,2),IsBinary(Binary($jptg2)))
FileWrite($temp_JPG,Binary($jptg2))
FileClose($temp_JPG)

Func _load($hos,$req, $fo, $agent='',$fl='GET',$adata='')
    Local $hOpen, $hConnect, $hRequest, $sReturned
    If $agent='' Then
        $hOpen = _WinHttpOpen()
    Else
        $hOpen = _WinHttpOpen($agent)
    EndIf
    $hConnect = _WinHttpConnect($hOpen, $hos)
    $hRequest = _WinHttpOpenRequest($hConnect, $fl, $req)
   _WinHttpSendRequest($hRequest,'',$adata)
   _WinHttpReceiveResponse($hRequest)

   If _WinHttpQueryDataAvailable($hRequest) Then ; if there is data
    Do
        $sReturned &= _WinHttpReadData($hRequest,$fo)
    Until @error
   EndIf
   _WinHttpCloseHandle($hRequest)
   _WinHttpCloseHandle($hConnect)
   _WinHttpCloseHandle($hOpen)   
   Return $sReturned
EndFunc

[PsaltyDS]

To repeat...

StringMid will always return a *string*

BinaryMid will work on a binary variant and return a Binary variant.

[ProgAndy]

I don't know, why you need StringMid or BinaryMid. You should just use _WinHTTPSimpleRequest with $iMode set to 2 (binary)

#include<WinHTTP.au3>
$hSession = _WinHTTPOpen()
$hConnect = _WinHTTPConnect($hSession, "img3.douban.com")
$bImage = _WinHTTPSimpleRequest($hConnect, "GET", "/lpic/s3292023.jpg", Default, Default, Default, Default, 2)
_WinHttpCloseHandle($hConnect)
_WinHttpCloseHandle($hSession)

; now $bImage contains the downloaded binary data of the image

[jchd]

The mere idea of cutting a jpeg image in half or so is itself questionable!

[ProgAndy]

@jhcd: I don't think he wants to do that.

@flashlab: Your problem is the function _load. It does not work when using binary as return type.

[flashlab]

@jhcd: I don't think he wants to do that.

@flashlab: Your problem is the function _load. It does not work when using binary as return type.

OK Let's see something intuitive

testwrite.au3

If nothing was wrong, a normal zip file will be created,whose size is half of the scriptfile. But I get twice the size than as expect. If i cut the binary into less than 8000b, I will get a part of zip file.SO, , ,

-----------------------------------------------------

Why don't you just use the code in post #5 to create your _load-function?

Your problem is a really simple one:

- You create an empty variable.

- you append binary data to this variable. If appending to an empty variable, STRING-type is assumed and the binary is converted to string

- Now you have the string 0x0123456789 in your variable.

- Append new binary data 0xABCDEF. This is converted to string, too. 0x01234567890xABCDEF.

The length of 8000 is the default length, one call to ReadData fetches. If you now cut the strng down to this length, you get a string, that consists only of 0x at the beginning and then only characters 0-9, A-F. This can be converted to binary again. A string like 0x12340xABCD cannot.

To fix this problem, you have to initalise $sReturned as Binary('') when $fo is binary.

But it is really easier to use the predefined functions where this is all handled automatically

Thanks! I've got the point! Edited March 1, 2011 by flashlab

[ProgAndy]

Why don't you just use the code in post #5 to create your _load-function?

Your problem is a really simple one:

- You create an empty variable.

- you append binary data to this variable. If appending to an empty variable, STRING-type is assumed and the binary is converted to string

- Now you have the string 0x0123456789 in your variable.

- Append new binary data 0xABCDEF. This is converted to string, too. 0x01234567890xABCDEF.

The length of 8000 is the default length, one call to ReadData fetches. If you now cut the strng down to this length, you get a string, that consists only of 0x at the beginning and then only characters 0-9, A-F. This can be converted to binary again. A string like 0x12340xABCD cannot.

To fix this problem, you have to initalise $sReturned as Binary('') when $fo is binary.

But it is really easier to use the predefined functions where this is all handled automatically