之前,我负责一个VB6编写的办公自动化系统,要求能在运行时,支持在不同语言间切换(英文,中文,日文,德文,法文和西班牙文);实质就是实现一个VB6的MUI程序.

这个需要的困难在于VB6显示文本的标准控件(Label,Textbox等)不支持Unicode;但字符串在其内部是按Unicode保存的,也就是说VB6本身是支持Unicode的.

VB6中,标准控件显示字符串的过程如下:

1) 标准控件先将Unicode字符串转换成ANSI字符串;

2) 标准控件尝试将ANSI字符串转换成其Font.Charset属性中指定的字符集格式的字符串;如果转换失败,则显示为问号(?).

具体可参照:Display Unicode Strings in Visual Basic 6.0.

因此,实现MUI程序的思路有两种:

1) 将标准控件替换为能支持Unicode的控件;

2) 将资源文件中不同字符集的文本,转换为ANSI格式,提供给标准控件使用;

第1)种方式可用 Forms 2.0 (fm20.dll);

第2)种方式,我在网上找到两篇文章,但各有不足:

a) Auto-Detect Language and Display Unicode in VB6 TextBox and Label Controls;

ChilkatCharset2控件需购买,具对日文的一些标点符号(如全角句号)不支持.

b) How To Convert from ANSI to Unicode & Unicode to ANSI for OLE

没有测试成功.

下面,着重介绍我自己认为比较成功的实现,它使用了ADODB.Stream(msado25.tlb);其实现思路如下:

1) 将程序中用到的文本保存为Unicode格式的资源文件中;

之所以将资源文本保存为双字节的Unicode格式,而非Utf8或Utf7格式,可省去从其它格式向VB6支持的Unicode格式转换过程.

2) 将显示文本的标准控件的Font.Charset,设置为程序要显示语言所对应的字符集,并设置一种支持这种字符集的字体到Font.Name属性

If g_Str.NumJapanese > 0 Then

charset = "Shift_JIS"

Text1.Font.Name = "MS UI Gothic"

Text1.Font.charset = 128

ElseIf g_Str.NumKorean > 0 Then

charset = "ks_c_5601-1987"

Text1.Font.Name = "GulimChe"

Text1.Font.charset = 129

ElseIf g_Str.NumCentralEuro > 0 Then

charset = "windows-1250"

Text1.Font.Name = "Arial"

Text1.Font.charset = 238

ElseIf g_Str.NumArabic > 0 Then

charset = "windows-1256"

Text1.Font.Name = "Traditional Arabic"

Text1.Font.charset = 178

ElseIf g_Str.NumHebrew > 0 Then

charset = "windows-1255"

Text1.Font.Name = "David"

Text1.Font.charset = 177

ElseIf g_Str.NumCyrillic > 0 Then

charset = "windows-1251"

Text1.Font.Name = "Arial"

Text1.Font.charset = 204

ElseIf g_Str.NumGreek > 0 Then

charset = "windows-1253"

Text1.Font.Name = "Arial"

Text1.Font.charset = 161

ElseIf g_Str.NumThai > 0 Then

charset = "windows-874"

Text1.Font.Name = "Angsana New"

Text1.Font.charset = 222

ElseIf g_Str.NumChinese > 0 Then

charset = "gb2312"

Text1.Font.Name = "SimSun"

Text1.Font.charset = 134

' An alternative is to use Big5:

' Text1.Font.Name = "MingLiu"

'charset = "big5"

'fontCh = 136

Else

charset = "windows-1252"

Text1.Font.charset = 0

Text1.Font.Name = "Arial" End If 3)

根据要显示的语言,利用ADODB.Stream将资源文件中Unicode格式保存的字符串转换成操作系统的区域语言(Locale)支持字符集的字符串;

' 调用API来获取操作系统默认的区域语言设置(LocaleID)

Private Declare Function GetSystemDefaultLCID Lib "kernel32" () As Long

' 将Unicode字符串,转换为指定字符集的字节数组;

' 用于转换用资源文件中读取的文本;

Public Function ConvertStringToBytes(ByRef strText As String, charset As String) As Byte()

Dim objStream As ADODB.Stream

Dim data() As Byte

' init stream

Set objStream = New ADODB.Stream

objStream.charset = charset

objStream.Mode = adModeReadWrite

objStream.Type = adTypeText

objStream.Open

' write bytes into stream

objStream.WriteText strText

objStream.Flush

' rewind stream and read text

objStream.Position = 0

objStream.Type = adTypeBinary '

objStream.Read 3 ' skip first 3 bytes as this is the utf-8 marker

data = objStream.Read()

' close up and return

objStream.Close

ConvertStringToUtf8Bytes = data

End Function '

转换为指定字符集的字节数组,转换为ANSI(即LocaleID)对应的字符集的字符串; ' 用于将ConvertStringToBytes()返回的字节数组转换为GetCharset()字符集的字符串.

Public Function ConvertBytesToString(ByRef data() As Byte, charset As String) As String

Dim objStream As ADODB.Stream

Dim strTmp As String

' init stream

Set objStream = New ADODB.Stream

objStream.charset = charset

objStream.Mode = adModeReadWrite

objStream.Type = adTypeBinary

objStream.Open

' write bytes into stream

objStream.Write data

objStream.Flush

' rewind stream and read text

objStream.Position = 0

objStream.Type = adTypeText

strTmp = objStream.ReadText

' close up and return

objStream.Close

ConvertUtf8BytesToString = strTmp

End Function

'获取操作系统默认区域语言对应的字符集

Public Function GetCharset() As String

Dim localeId As Long

Dim charset As String

' 获取操作系统的LocaleId

localeId = GetSystemDefaultLCID()

Select Case localeId

Case 1033

charset = "windows-1252"

Case 2052

charset = "gb2312"

Case 1041

charset = "Shift_JIS"

Case Else

charset = "windows-1252"

End Select

GetCharset = charset End Function

'显示资源文本中的文本

Private Sub DisplayText(filename As String)

'保存资源文本中的文本的变量

Dim textBytes As Variant

Dim f As New FileSystemObject

Dim fs As TextStream

'将Unicode文本读取到变量中

Set fs = f.OpenTextFile(filename, ForReading, False, TristateTrue)

Do While Not fs.AtEndOfStream

textBytes = fs.ReadAll

Loop fs.Close

' Convert to a Unicode string:

Dim s As String

s = textBytes

Dim t As Long

' CkString是免费的第三方组件,可自动判定一个字符串所对应的字符集

' 下载地址:http://www.chilkatsoft.com/download/CkString.zip

Dim g_Str As New CkString

g_Str.Str = s

'获取资源文本所代表的字符集名称,设置对应的字体和字符集到textbox上

Dim charset As String

If g_Str.NumJapanese > 0 Then '日文

charset = "Shift_JIS"

Text1.Font.Name = "MS UI Gothic"

Text1.Font.charset = 128

ElseIf g_Str.NumKorean > 0 Then '韩语

charset = "ks_c_5601-1987"

Text1.Font.Name = "GulimChe"

Text1.Font.charset = 129

ElseIf g_Str.NumCentralEuro > 0 Then '中欧语言

charset = "windows-1250"

Text1.Font.Name = "Arial"

Text1.Font.charset = 238

ElseIf g_Str.NumArabic > 0 Then '阿拉伯语

charset = "windows-1256"

Text1.Font.Name = "Traditional Arabic"

Text1.Font.charset = 178

ElseIf g_Str.NumGreek > 0 Then '希腊语

charset = "windows-1253"

Text1.Font.Name = "Arial"

Text1.Font.charset = 161

ElseIf g_Str.NumThai > 0 Then '泰语

charset = "windows-874"

Text1.Font.Name = "Angsana New"

Text1.Font.charset = 222

ElseIf g_Str.NumChinese > 0 Then '中文

charset = "gb2312"

Text1.Font.Name = "SimSun"

Text1.Font.charset = 134

' 繁体则使用Big5:

' Text1.Font.Name = "MingLiu"

'charset = "big5"

'Text1.Font.charset = 136

Else '默认值

charset = "windows-1252"

Text1.Font.charset = 0

Text1.Font.Name = "Arial"

End If

Dim bytes() As Byte

Dim g_OSCharset As String

'获取操作系统默认语言对应的字符集

g_OSCharset = GetCharset()

'先将Unicode资源文本转换成对应的字节数组;

bytes = ConvertStringToBytes(s, charset)

'将字节数组转换成ANSI(即默认字符集)对应的字符串

vbstr2 = ConvertBytesToString(bytes, g_OSCharset)

' 设置字符串到VB6的标准控件中

Me.Text1.Text = vbstr2 End Sub

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