之前,我負責一個VB6編寫的辦公自動化系統,要求能在運行時,支持在不同語言間切換(英文,中文,日文,德文,法文和西班牙文);實質就是實現一個VB6的MUI程序.
這個需要的困難在於VB6顯示文本的標准控件(Label,Textbox等)不支持Unicode;但字符串在其內部是按Unicode保存的,也就是說VB6本身是支持Unicode的.
VB6中,標准控件顯示字符串的過程如下:
1) 標准控件先將Unicode字符串轉換成ANSI字符串;
2) 標准控件嘗試將ANSI字符串轉換成其Font.Charset屬性中指定的字符集格式的字符串;如果轉換失敗,則顯示為問號(?).
具體可參照:Display Unicode Strings in Visual Basic 6.0.
因此,實現MUI程序的思路有兩種:
1) 將標准控件替換為能支持Unicode的控件;
2) 將資源文件中不同字符集的文本,轉換為ANSI格式,提供給標准控件使用;
第1)種方式可用 Forms 2.0 (fm20.dll);
第2)種方式,我在網上找到兩篇文章,但各有不足:
a) Auto-Detect Language and Display Unicode in VB6 TextBox and Label Controls;
ChilkatCharset2控件需購買,具對日文的一些標點符號(如全角句號)不支持.
b) How To Convert from ANSI to Unicode & Unicode to ANSI for OLE
沒有測試成功.
下面,著重介紹我自己認為比較成功的實現,它使用了ADODB.Stream(msado25.tlb);其實現思路如下:
1) 將程序中用到的文本保存為Unicode格式的資源文件中;
之所以將資源文本保存為雙字節的Unicode格式,而非Utf8或Utf7格式,可省去從其它格式向VB6支持的Unicode格式轉換過程.
2) 將顯示文本的標准控件的Font.Charset,設置為程序要顯示語言所對應的字符集,並設置一種支持這種字符集的字體到Font.Name屬性
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)
根據要顯示的語言,利用ADODB.Stream將資源文件中Unicode格式保存的字符串轉換成操作系統的區域語言(Locale)支持字符集的字符串;
' 調用API來獲取操作系統默認的區域語言設置(LocaleID)
Private Declare Function GetSystemDefaultLCID Lib "kernel32" () As Long
' 將Unicode字符串,轉換為指定字符集的字節數組;
' 用於轉換用資源文件中讀取的文本;
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 '
轉換為指定字符集的字節數組,轉換為ANSI(即LocaleID)對應的字符集的字符串; ' 用於將ConvertStringToBytes()返回的字節數組轉換為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
'獲取操作系統默認區域語言對應的字符集
Public Function GetCharset() As String
Dim localeId As Long
Dim charset As String
' 獲取操作系統的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
'顯示資源文本中的文本
Private Sub DisplayText(filename As String)
'保存資源文本中的文本的變量
Dim textBytes As Variant
Dim f As New FileSystemObject
Dim fs As TextStream
'將Unicode文本讀取到變量中
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是免費的第三方組件,可自動判定一個字符串所對應的字符集
' 下載地址:http://www.chilkatsoft.com/download/CkString.zip
Dim g_Str As New CkString
g_Str.Str = s
'獲取資源文本所代表的字符集名稱,設置對應的字體和字符集到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 '韓語
charset = "ks_c_5601-1987"
Text1.Font.Name = "GulimChe"
Text1.Font.charset = 129
ElseIf g_Str.NumCentralEuro > 0 Then '中歐語言
charset = "windows-1250"
Text1.Font.Name = "Arial"
Text1.Font.charset = 238
ElseIf g_Str.NumArabic > 0 Then '阿拉伯語
charset = "windows-1256"
Text1.Font.Name = "Traditional Arabic"
Text1.Font.charset = 178
ElseIf g_Str.NumGreek > 0 Then '希臘語
charset = "windows-1253"
Text1.Font.Name = "Arial"
Text1.Font.charset = 161
ElseIf g_Str.NumThai > 0 Then '泰語
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
' 繁體則使用Big5:
' Text1.Font.Name = "MingLiu"
'charset = "big5"
'Text1.Font.charset = 136
Else '默認值
charset = "windows-1252"
Text1.Font.charset = 0
Text1.Font.Name = "Arial"
End If
Dim bytes() As Byte
Dim g_OSCharset As String
'獲取操作系統默認語言對應的字符集
g_OSCharset = GetCharset()
'先將Unicode資源文本轉換成對應的字節數組;
bytes = ConvertStringToBytes(s, charset)
'將字節數組轉換成ANSI(即默認字符集)對應的字符串
vbstr2 = ConvertBytesToString(bytes, g_OSCharset)
' 設置字符串到VB6的標准控件中
Me.Text1.Text = vbstr2 End Sub
