Mikel
asp环境中，vbscript先天性的在读写二进制数据方面比JScript方便，JScript本身并无针对二进制数据（或者说字节数据）的数 据类型、对象、方法，所以有些高手爱用JScript写ASP，但是如果涉及字节数据处理基本上都要头痛。我在CodeProject.com上看到这篇 文章，觉得非常有用，所以转过来。基本原理就是用ADODB.Stream读写时指定为437代码页就可以以文本的形式来读写了。
原文网址： http://www.codeproject.com/KB/scripting/Exsead7.aspx
Reading And Writing Binary Files Using JScript
|
By alex turner An easy to use class that gives some binary file abilities to JScript |
JavaScript, Windows, Visual Studio, Dev |
Note: This is an unedited contribution. If this article is inappropriate, needs attention or copies someone else's work without reference then please Report This Article
Introduction
As I have pushed what I can do in JScript, I have come up against the issue of binary files. The following class solved this for small to medium size files. I am partly including this post here because I am about to put in a post about sending emails with attachments via JScript and it will use this binary file code to read in the binary attachment files.
So, here is a nice way of accessing binary files from JScript. If you want to access this object from VBScript, then put it in a swf file. This object has been used in anger to upload files to a web service and has proven to be nice and fast for files in the 0-10 MByte region.
/** This is a fairly well optimized object which alows
* access to binary files from JScript on a Windows
* operating system.
*
* A the end of the file is small set of tests to show how it
* is used. You will require ADODB 2.5 or higher installed.
* this will be so on most 2000 machines and all XP or higher
* machines.
*
* CopyRight: Dr Alexander J Turner – all rights reserved.
* Please feel free to use this code in any way you like
* as long as you place a reference in the comments that
* I wrote it.
*/
function BinaryFile(name)
{
var adTypeBinary = 1
var adTypeText = 2
var adSaveCreateOverWrite = 2
// The trick – this is the 'old fassioned' not translation page
// It lest JavaScript use strings to act like raw octets
var codePage='437';
this.path=name;
var forward = new Array();
var backward = new Array();
// Note – for better performance I should preconvert these hex
// definitions to decimal – at some point 🙂 – AJT
forward['80'] = '00C7';
forward['81'] = '00FC';
forward['82'] = '00E9';
forward['83'] = '00E2';
forward['84'] = '00E4';
forward['85'] = '00E0';
forward['86'] = '00E5';
forward['87'] = '00E7';
forward['88'] = '00EA';
forward['89'] = '00EB';
forward['8A'] = '00E8';
forward['8B'] = '00EF';
forward['8C'] = '00EE';
forward['8D'] = '00EC';
forward['8E'] = '00C4';
forward['8F'] = '00C5';
forward['90'] = '00C9';
forward['91'] = '00E6';
forward['92'] = '00C6';
forward['93'] = '00F4';
forward['94'] = '00F6';
forward['95'] = '00F2';
forward['96'] = '00FB';
forward['97'] = '00F9';
forward['98'] = '00FF';
forward['99'] = '00D6';
forward['9A'] = '00DC';
forward['9B'] = '00A2';
forward['9C'] = '00A3';
forward['9D'] = '00A5';
forward['9E'] = '20A7';
forward['9F'] = '0192';
forward['A0'] = '00E1';
forward['A1'] = '00ED';
forward['A2'] = '00F3';
forward['A3'] = '00FA';
forward['A4'] = '00F1';
forward['A5'] = '00D1';
forward['A6'] = '00AA';
forward['A7'] = '00BA';
forward['A8'] = '00BF';
forward['A9'] = '2310';
forward['AA'] = '00AC';
forward['AB'] = '00BD';
forward['AC'] = '00BC';
forward['AD'] = '00A1';
forward['AE'] = '00AB';
forward['AF'] = '00BB';
forward['B0'] = '2591';
forward['B1'] = '2592';
forward['B2'] = '2593';
forward['B3'] = '2502';
forward['B4'] = '2524';
forward['B5'] = '2561';
forward['B6'] = '2562';
forward['B7'] = '2556';
forward['B8'] = '2555';
forward['B9'] = '2563';
forward['BA'] = '2551';
forward['BB'] = '2557';
forward['BC'] = '255D';
forward['BD'] = '255C';
forward['BE'] = '255B';
forward['BF'] = '2510';
forward['C0'] = '2514';
forward['C1'] = '2534';
forward['C2'] = '252C';
forward['C3'] = '251C';
forward['C4'] = '2500';
forward['C5'] = '253C';
forward['C6'] = '255E';
forward['C7'] = '255F';
forward['C8'] = '255A';
forward['C9'] = '2554';
forward['CA'] = '2569';
forward['CB'] = '2566';
forward['CC'] = '2560';
forward['CD'] = '2550';
forward['CE'] = '256C';
forward['CF'] = '2567';
forward['D0'] = '2568';
forward['D1'] = '2564';
forward['D2'] = '2565';
forward['D3'] = '2559';
forward['D4'] = '2558';
forward['D5'] = '2552';
forward['D6'] = '2553';
forward['D7'] = '256B';
forward['D8'] = '256A';
forward['D9'] = '2518';
forward['DA'] = '250C';
forward['DB'] = '2588';
forward['DC'] = '2584';
forward['DD'] = '258C';
forward['DE'] = '2590';
forward['DF'] = '2580';
forward['E0'] = '03B1';
forward['E1'] = '00DF';
forward['E2'] = '0393';
forward['E3'] = '03C0';
forward['E4'] = '03A3';
forward['E5'] = '03C3';
forward['E6'] = '00B5';
forward['E7'] = '03C4';
forward['E8'] = '03A6';
forward['E9'] = '0398';
forward['EA'] = '03A9';
forward['EB'] = '03B4';
forward['EC'] = '221E';
forward['ED'] = '03C6';
forward['EE'] = '03B5';
forward['EF'] = '2229';
forward['F0'] = '2261';
forward['F1'] = '00B1';
forward['F2'] = '2265';
forward['F3'] = '2264';
forward['F4'] = '2320';
forward['F5'] = '2321';
forward['F6'] = '00F7';
forward['F7'] = '2248';
forward['F8'] = '00B0';
forward['F9'] = '2219';
forward['FA'] = '00B7';
forward['FB'] = '221A';
forward['FC'] = '207F';
forward['FD'] = '00B2';
forward['FE'] = '25A0';
forward['FF'] = '00A0';
backward['C7'] = '80';
backward['FC'] = '81';
backward['E9'] = '82';
backward['E2'] = '83';
backward['E4'] = '84';
backward['E0'] = '85';
backward['E5'] = '86';
backward['E7'] = '87';
backward['EA'] = '88';
backward['EB'] = '89';
backward['E8'] = '8A';
backward['EF'] = '8B';
backward['EE'] = '8C';
backward['EC'] = '8D';
backward['C4'] = '8E';
backward['C5'] = '8F';
backward['C9'] = '90';
backward['E6'] = '91';
backward['C6'] = '92';
backward['F4'] = '93';
backward['F6'] = '94';
backward['F2'] = '95';
backward['FB'] = '96';
backward['F9'] = '97';
backward['FF'] = '98';
backward['D6'] = '99';
backward['DC'] = '9A';
backward['A2'] = '9B';
backward['A3'] = '9C';
backward['A5'] = '9D';
backward['20A7'] = '9E';
backward['192'] = '9F';
backward['E1'] = 'A0';
backward['ED'] = 'A1';
backward['F3'] = 'A2';
backward['FA'] = 'A3';
backward['F1'] = 'A4';
backward['D1'] = 'A5';
backward['AA'] = 'A6';
backward['BA'] = 'A7';
backward['BF'] = 'A8';
backward['2310'] = 'A9';
backward['AC'] = 'AA';
backward['BD'] = 'AB';
backward['BC'] = 'AC';
backward['A1'] = 'AD';
backward['AB'] = 'AE';
backward['BB'] = 'AF';
backward['2591'] = 'B0';
backward['2592'] = 'B1';
backward['2593'] = 'B2';
backward['2502'] = 'B3';
backward['2524'] = 'B4';
backward['2561'] = 'B5';
backward['2562'] = 'B6';
backward['2556'] = 'B7';
backward['2555'] = 'B8';
backward['2563'] = 'B9';
backward['2551'] = 'BA';
backward['2557'] = 'BB';
backward['255D'] = 'BC';
backward['255C'] = 'BD';
backward['255B'] = 'BE';
backward['2510'] = 'BF';
backward['2514'] = 'C0';
backward['2534'] = 'C1';
backward['252C'] = 'C2';
backward['251C'] = 'C3';
backward['2500'] = 'C4';
backward['253C'] = 'C5';
backward['255E'] = 'C6';
backward['255F'] = 'C7';
backward['255A'] = 'C8';
backward['2554'] = 'C9';
backward['2569'] = 'CA';
backward['2566'] = 'CB';
backward['2560'] = 'CC';
backward['2550'] = 'CD';
backward['256C'] = 'CE';
backward['2567'] = 'CF';
backward['2568'] = 'D0';
backward['2564'] = 'D1';
backward['2565'] = 'D2';
backward['2559'] = 'D3';
backward['2558'] = 'D4';
backward['2552'] = 'D5';
backward['2553'] = 'D6';
backward['256B'] = 'D7';
backward['256A'] = 'D8';
backward['2518'] = 'D9';
backward['250C'] = 'DA';
backward['2588'] = 'DB';
backward['2584'] = 'DC';
backward['258C'] = 'DD';
backward['2590'] = 'DE';
backward['2580'] = 'DF';
backward['3B1'] = 'E0';
backward['DF'] = 'E1';
backward['393'] = 'E2';
backward['3C0'] = 'E3';
backward['3A3'] = 'E4';
backward['3C3'] = 'E5';
backward['B5'] = 'E6';
backward['3C4'] = 'E7';
backward['3A6'] = 'E8';
backward['398'] = 'E9';
backward['3A9'] = 'EA';
backward['3B4'] = 'EB';
backward['221E'] = 'EC';
backward['3C6'] = 'ED';
backward['3B5'] = 'EE';
backward['2229'] = 'EF';
backward['2261'] = 'F0';
backward['B1'] = 'F1';
backward['2265'] = 'F2';
backward['2264'] = 'F3';
backward['2320'] = 'F4';
backward['2321'] = 'F5';
backward['F7'] = 'F6';
backward['2248'] = 'F7';
backward['B0'] = 'F8';
backward['2219'] = 'F9';
backward['B7'] = 'FA';
backward['221A'] = 'FB';
backward['207F'] = 'FC';
backward['B2'] = 'FD';
backward['25A0'] = 'FE';
backward['A0'] = 'FF';
var hD="0123456789ABCDEF";
this.d2h = function(d)
{
var h = hD.substr(d&15,1);
while(d>15) {d>>=4;h=hD.substr(d&15,1)+h;}
return h;
}
this.h2d = function(h)
{
return parseInt(h,16);
}
this.WriteAll = function(what)
{
//Create Stream object
var BinaryStream = WScript.CreateObject("ADODB.Stream");
//Specify stream type – we cheat and get string but 'like' binary
BinaryStream.Type = adTypeText;
BinaryStream.CharSet = '437';
//Open the stream
BinaryStream.Open();
// Write to the stream
BinaryStream.WriteText(this.Forward437(what));
// Write the string to the disk
BinaryStream.SaveToFile(this.path, adSaveCreateOverWrite);
// Clearn up
BinaryStream.Close();
}
this.ReadAll = function()
{
//Create Stream object – needs ADO 2.5 or heigher
var BinaryStream = WScript.CreateObject("ADODB.Stream")
//Specify stream type – we cheat and get string but 'like' binary
BinaryStream.Type = adTypeText;
BinaryStream.CharSet = codePage;
//Open the stream
BinaryStream.Open();
//Load the file data from disk To stream object
BinaryStream.LoadFromFile(this.path);
//Open the stream And get binary 'string' from the object
var what = BinaryStream.ReadText;
// Clean up
BinaryStream.Close();
return this.Backward437(what);
}
/* Convert a octet number to a code page 437 char code */
this.Forward437 = function(inString)
{
var encArray = new Array();
var tmp='';
var i=0;
var c=0;
var l=inString.length;
var cc;
var h;
for(;i<l;++i)
{
c++;
if(c==128)
{
encArray.push(tmp);
tmp='';
c=0;
}
cc=inString.charCodeAt(i);
if(cc<128)
{
tmp+=String.fromCharCode(cc);
}
else
{
h=this.d2h(cc);
h=forward[''+h];
tmp+=String.fromCharCode(this.h2d(h));
}
}
if(tmp!='')
{
encArray.push(tmp);
}
// this loop progressive concatonates the
// array elements entil there is only one
var ar2=new Array();
for(;encArray.length>1😉
{
var l=encArray.length;
for(var c=0;c<l;c+=2)
{
if(c+1==l)
{
ar2.push(encArray);
}
else
{
ar2.push(''+encArray+encArray);
}
}
encArray=ar2;
ar2=new Array();
}
return encArray[0];
}
/* Convert a code page 437 char code to a octet number*/
this.Backward437 = function(inString)
{
var encArray = new Array();
var tmp='';
var i=0;
var c=0;
var l=inString.length;
var cc;
var h;
for(;i<l;++i)
{
c++;
if(c==128)
{
encArray.push(tmp);
tmp='';
c=0;
}
cc=inString.charCodeAt(i);
if(cc<128)
{
tmp+=String.fromCharCode(cc);
}
else
{
h=this.d2h(cc);
h=backward[''+h];
tmp+=String.fromCharCode(this.h2d(h));
}
}
if(tmp!='')
{
encArray.push(tmp);
}
// this loop progressive concatonates the
// array elements entil there is only one
var ar2=new Array();
for(;encArray.length>1😉
{
var l=encArray.length;
for(var c=0;c<l;c+=2)
{
if(c+1==l)
{
ar2.push(encArray);
}
else
{
ar2.push(''+encArray+encArray);
}
}
encArray=ar2;
ar2=new Array();
}
return encArray[0];
}
}
// Example Code
/*
var bf0=new BinaryFile();
var crFolder = 'C:/Temp/cr'
var bf1=new BinaryFile(crFolder+"/PCDV0026.JPG");
var bf2=new BinaryFile(crFolder+"/PCDV0026_.JPG");
bf2.WriteAll(bf1.ReadAll());
*/
* access to binary files from JScript on a Windows
* operating system.
*
* A the end of the file is small set of tests to show how it
* is used. You will require ADODB 2.5 or higher installed.
* this will be so on most 2000 machines and all XP or higher
* machines.
*
* CopyRight: Dr Alexander J Turner – all rights reserved.
* Please feel free to use this code in any way you like
* as long as you place a reference in the comments that
* I wrote it.
*/
function BinaryFile(name)
{
var adTypeBinary = 1
var adTypeText = 2
var adSaveCreateOverWrite = 2
// The trick – this is the 'old fassioned' not translation page
// It lest JavaScript use strings to act like raw octets
var codePage='437';
this.path=name;
var forward = new Array();
var backward = new Array();
// Note – for better performance I should preconvert these hex
// definitions to decimal – at some point 🙂 – AJT
forward['80'] = '00C7';
forward['81'] = '00FC';
forward['82'] = '00E9';
forward['83'] = '00E2';
forward['84'] = '00E4';
forward['85'] = '00E0';
forward['86'] = '00E5';
forward['87'] = '00E7';
forward['88'] = '00EA';
forward['89'] = '00EB';
forward['8A'] = '00E8';
forward['8B'] = '00EF';
forward['8C'] = '00EE';
forward['8D'] = '00EC';
forward['8E'] = '00C4';
forward['8F'] = '00C5';
forward['90'] = '00C9';
forward['91'] = '00E6';
forward['92'] = '00C6';
forward['93'] = '00F4';
forward['94'] = '00F6';
forward['95'] = '00F2';
forward['96'] = '00FB';
forward['97'] = '00F9';
forward['98'] = '00FF';
forward['99'] = '00D6';
forward['9A'] = '00DC';
forward['9B'] = '00A2';
forward['9C'] = '00A3';
forward['9D'] = '00A5';
forward['9E'] = '20A7';
forward['9F'] = '0192';
forward['A0'] = '00E1';
forward['A1'] = '00ED';
forward['A2'] = '00F3';
forward['A3'] = '00FA';
forward['A4'] = '00F1';
forward['A5'] = '00D1';
forward['A6'] = '00AA';
forward['A7'] = '00BA';
forward['A8'] = '00BF';
forward['A9'] = '2310';
forward['AA'] = '00AC';
forward['AB'] = '00BD';
forward['AC'] = '00BC';
forward['AD'] = '00A1';
forward['AE'] = '00AB';
forward['AF'] = '00BB';
forward['B0'] = '2591';
forward['B1'] = '2592';
forward['B2'] = '2593';
forward['B3'] = '2502';
forward['B4'] = '2524';
forward['B5'] = '2561';
forward['B6'] = '2562';
forward['B7'] = '2556';
forward['B8'] = '2555';
forward['B9'] = '2563';
forward['BA'] = '2551';
forward['BB'] = '2557';
forward['BC'] = '255D';
forward['BD'] = '255C';
forward['BE'] = '255B';
forward['BF'] = '2510';
forward['C0'] = '2514';
forward['C1'] = '2534';
forward['C2'] = '252C';
forward['C3'] = '251C';
forward['C4'] = '2500';
forward['C5'] = '253C';
forward['C6'] = '255E';
forward['C7'] = '255F';
forward['C8'] = '255A';
forward['C9'] = '2554';
forward['CA'] = '2569';
forward['CB'] = '2566';
forward['CC'] = '2560';
forward['CD'] = '2550';
forward['CE'] = '256C';
forward['CF'] = '2567';
forward['D0'] = '2568';
forward['D1'] = '2564';
forward['D2'] = '2565';
forward['D3'] = '2559';
forward['D4'] = '2558';
forward['D5'] = '2552';
forward['D6'] = '2553';
forward['D7'] = '256B';
forward['D8'] = '256A';
forward['D9'] = '2518';
forward['DA'] = '250C';
forward['DB'] = '2588';
forward['DC'] = '2584';
forward['DD'] = '258C';
forward['DE'] = '2590';
forward['DF'] = '2580';
forward['E0'] = '03B1';
forward['E1'] = '00DF';
forward['E2'] = '0393';
forward['E3'] = '03C0';
forward['E4'] = '03A3';
forward['E5'] = '03C3';
forward['E6'] = '00B5';
forward['E7'] = '03C4';
forward['E8'] = '03A6';
forward['E9'] = '0398';
forward['EA'] = '03A9';
forward['EB'] = '03B4';
forward['EC'] = '221E';
forward['ED'] = '03C6';
forward['EE'] = '03B5';
forward['EF'] = '2229';
forward['F0'] = '2261';
forward['F1'] = '00B1';
forward['F2'] = '2265';
forward['F3'] = '2264';
forward['F4'] = '2320';
forward['F5'] = '2321';
forward['F6'] = '00F7';
forward['F7'] = '2248';
forward['F8'] = '00B0';
forward['F9'] = '2219';
forward['FA'] = '00B7';
forward['FB'] = '221A';
forward['FC'] = '207F';
forward['FD'] = '00B2';
forward['FE'] = '25A0';
forward['FF'] = '00A0';
backward['C7'] = '80';
backward['FC'] = '81';
backward['E9'] = '82';
backward['E2'] = '83';
backward['E4'] = '84';
backward['E0'] = '85';
backward['E5'] = '86';
backward['E7'] = '87';
backward['EA'] = '88';
backward['EB'] = '89';
backward['E8'] = '8A';
backward['EF'] = '8B';
backward['EE'] = '8C';
backward['EC'] = '8D';
backward['C4'] = '8E';
backward['C5'] = '8F';
backward['C9'] = '90';
backward['E6'] = '91';
backward['C6'] = '92';
backward['F4'] = '93';
backward['F6'] = '94';
backward['F2'] = '95';
backward['FB'] = '96';
backward['F9'] = '97';
backward['FF'] = '98';
backward['D6'] = '99';
backward['DC'] = '9A';
backward['A2'] = '9B';
backward['A3'] = '9C';
backward['A5'] = '9D';
backward['20A7'] = '9E';
backward['192'] = '9F';
backward['E1'] = 'A0';
backward['ED'] = 'A1';
backward['F3'] = 'A2';
backward['FA'] = 'A3';
backward['F1'] = 'A4';
backward['D1'] = 'A5';
backward['AA'] = 'A6';
backward['BA'] = 'A7';
backward['BF'] = 'A8';
backward['2310'] = 'A9';
backward['AC'] = 'AA';
backward['BD'] = 'AB';
backward['BC'] = 'AC';
backward['A1'] = 'AD';
backward['AB'] = 'AE';
backward['BB'] = 'AF';
backward['2591'] = 'B0';
backward['2592'] = 'B1';
backward['2593'] = 'B2';
backward['2502'] = 'B3';
backward['2524'] = 'B4';
backward['2561'] = 'B5';
backward['2562'] = 'B6';
backward['2556'] = 'B7';
backward['2555'] = 'B8';
backward['2563'] = 'B9';
backward['2551'] = 'BA';
backward['2557'] = 'BB';
backward['255D'] = 'BC';
backward['255C'] = 'BD';
backward['255B'] = 'BE';
backward['2510'] = 'BF';
backward['2514'] = 'C0';
backward['2534'] = 'C1';
backward['252C'] = 'C2';
backward['251C'] = 'C3';
backward['2500'] = 'C4';
backward['253C'] = 'C5';
backward['255E'] = 'C6';
backward['255F'] = 'C7';
backward['255A'] = 'C8';
backward['2554'] = 'C9';
backward['2569'] = 'CA';
backward['2566'] = 'CB';
backward['2560'] = 'CC';
backward['2550'] = 'CD';
backward['256C'] = 'CE';
backward['2567'] = 'CF';
backward['2568'] = 'D0';
backward['2564'] = 'D1';
backward['2565'] = 'D2';
backward['2559'] = 'D3';
backward['2558'] = 'D4';
backward['2552'] = 'D5';
backward['2553'] = 'D6';
backward['256B'] = 'D7';
backward['256A'] = 'D8';
backward['2518'] = 'D9';
backward['250C'] = 'DA';
backward['2588'] = 'DB';
backward['2584'] = 'DC';
backward['258C'] = 'DD';
backward['2590'] = 'DE';
backward['2580'] = 'DF';
backward['3B1'] = 'E0';
backward['DF'] = 'E1';
backward['393'] = 'E2';
backward['3C0'] = 'E3';
backward['3A3'] = 'E4';
backward['3C3'] = 'E5';
backward['B5'] = 'E6';
backward['3C4'] = 'E7';
backward['3A6'] = 'E8';
backward['398'] = 'E9';
backward['3A9'] = 'EA';
backward['3B4'] = 'EB';
backward['221E'] = 'EC';
backward['3C6'] = 'ED';
backward['3B5'] = 'EE';
backward['2229'] = 'EF';
backward['2261'] = 'F0';
backward['B1'] = 'F1';
backward['2265'] = 'F2';
backward['2264'] = 'F3';
backward['2320'] = 'F4';
backward['2321'] = 'F5';
backward['F7'] = 'F6';
backward['2248'] = 'F7';
backward['B0'] = 'F8';
backward['2219'] = 'F9';
backward['B7'] = 'FA';
backward['221A'] = 'FB';
backward['207F'] = 'FC';
backward['B2'] = 'FD';
backward['25A0'] = 'FE';
backward['A0'] = 'FF';
var hD="0123456789ABCDEF";
this.d2h = function(d)
{
var h = hD.substr(d&15,1);
while(d>15) {d>>=4;h=hD.substr(d&15,1)+h;}
return h;
}
this.h2d = function(h)
{
return parseInt(h,16);
}
this.WriteAll = function(what)
{
//Create Stream object
var BinaryStream = WScript.CreateObject("ADODB.Stream");
//Specify stream type – we cheat and get string but 'like' binary
BinaryStream.Type = adTypeText;
BinaryStream.CharSet = '437';
//Open the stream
BinaryStream.Open();
// Write to the stream
BinaryStream.WriteText(this.Forward437(what));
// Write the string to the disk
BinaryStream.SaveToFile(this.path, adSaveCreateOverWrite);
// Clearn up
BinaryStream.Close();
}
this.ReadAll = function()
{
//Create Stream object – needs ADO 2.5 or heigher
var BinaryStream = WScript.CreateObject("ADODB.Stream")
//Specify stream type – we cheat and get string but 'like' binary
BinaryStream.Type = adTypeText;
BinaryStream.CharSet = codePage;
//Open the stream
BinaryStream.Open();
//Load the file data from disk To stream object
BinaryStream.LoadFromFile(this.path);
//Open the stream And get binary 'string' from the object
var what = BinaryStream.ReadText;
// Clean up
BinaryStream.Close();
return this.Backward437(what);
}
/* Convert a octet number to a code page 437 char code */
this.Forward437 = function(inString)
{
var encArray = new Array();
var tmp='';
var i=0;
var c=0;
var l=inString.length;
var cc;
var h;
for(;i<l;++i)
{
c++;
if(c==128)
{
encArray.push(tmp);
tmp='';
c=0;
}
cc=inString.charCodeAt(i);
if(cc<128)
{
tmp+=String.fromCharCode(cc);
}
else
{
h=this.d2h(cc);
h=forward[''+h];
tmp+=String.fromCharCode(this.h2d(h));
}
}
if(tmp!='')
{
encArray.push(tmp);
}
// this loop progressive concatonates the
// array elements entil there is only one
var ar2=new Array();
for(;encArray.length>1😉
{
var l=encArray.length;
for(var c=0;c<l;c+=2)
{
if(c+1==l)
{
ar2.push(encArray);
}
else
{
ar2.push(''+encArray+encArray);
}
}
encArray=ar2;
ar2=new Array();
}
return encArray[0];
}
/* Convert a code page 437 char code to a octet number*/
this.Backward437 = function(inString)
{
var encArray = new Array();
var tmp='';
var i=0;
var c=0;
var l=inString.length;
var cc;
var h;
for(;i<l;++i)
{
c++;
if(c==128)
{
encArray.push(tmp);
tmp='';
c=0;
}
cc=inString.charCodeAt(i);
if(cc<128)
{
tmp+=String.fromCharCode(cc);
}
else
{
h=this.d2h(cc);
h=backward[''+h];
tmp+=String.fromCharCode(this.h2d(h));
}
}
if(tmp!='')
{
encArray.push(tmp);
}
// this loop progressive concatonates the
// array elements entil there is only one
var ar2=new Array();
for(;encArray.length>1😉
{
var l=encArray.length;
for(var c=0;c<l;c+=2)
{
if(c+1==l)
{
ar2.push(encArray);
}
else
{
ar2.push(''+encArray+encArray);
}
}
encArray=ar2;
ar2=new Array();
}
return encArray[0];
}
}
// Example Code
/*
var bf0=new BinaryFile();
var crFolder = 'C:/Temp/cr'
var bf1=new BinaryFile(crFolder+"/PCDV0026.JPG");
var bf2=new BinaryFile(crFolder+"/PCDV0026_.JPG");
bf2.WriteAll(bf1.ReadAll());
*/
License
This article has no explicit license attached to it but may contain usage terms in the article text or the download files themselves. If in doubt please contact the author via the discussion board below.
A list of licenses authors might use can be found here
About the Author
| alex turner |
I started out as a Chemist, but just keep being pulled back into IT. I am now a senior architect with The Project Network (www.project-network.com)
|
