无需API密钥与多语言包，Excel VBA如何检测文本外语语种？

以下是几个无需API密钥、无需额外安装语言包的VBA解决方案：

1. 调用Google Translate匿名检测接口 #

通过构造Google Translate的内部检测请求，可直接获取语种代码，无需API密钥。该方案需联网，适合短文本检测：

Function DetectLanguage_Google(text As String) As String
    Dim xmlHttp As Object
    Dim response As String
    Dim jsonArr As Variant
    
    Set xmlHttp = CreateObject("MSXML2.XMLHTTP.6.0")
    ' 构造检测请求，dt=ld表示仅返回语种检测结果
    xmlHttp.Open "GET", "https://translate.googleapis.com/translate_a/single?client=gtx&dt=ld&q=" & URLEncode(text), False
    xmlHttp.Send
    
    response = xmlHttp.responseText
    ' 解析JSON数组（返回格式为[[["<语种代码>"]]]）
    jsonArr = Split(Split(response, "[[["")(1), """]]]")(0)
    DetectLanguage_Google = jsonArr
    
    Set xmlHttp = Nothing
End Function

' 辅助函数：URL编码
Function URLEncode(text As String) As String
    URLEncode = WorksheetFunction.EncodeURL(text)
End Function

2. 利用Windows系统MLang组件（离线检测） #

Windows自带的MLang多语言支持库可本地检测语种，无需联网和额外安装：

Function DetectLanguage_MLang(text As String) As String
    Dim mlang As Object
    Dim langId As Long
    Dim langCode As String
    
    Set mlang = CreateObject("MLanguage.MultiLanguage.2")
    ' 检测语种ID
    mlang.DetectString 0, text, Len(text), langId
    ' 将语种ID转换为ISO代码
    mlang.GetRfc1766Info langId, langCode
    
    DetectLanguage_MLang = Left(langCode, 2) '提取两位语种代码（如en、zh）
    Set mlang = Nothing
End Function

注意：该组件对部分小语种的检测准确率可能略低于在线接口，但胜在完全离线。

3. 调用Bing Translate匿名检测接口 #

通过构造Bing的翻译请求，解析返回结果中的语种信息：

Function DetectLanguage_Bing(text As String) As String
    Dim xmlHttp As Object
    Dim response As String
    Dim jsonStart As Integer
    Dim jsonEnd As Integer
    
    Set xmlHttp = CreateObject("MSXML2.XMLHTTP.6.0")
    xmlHttp.Open "POST", "https://www.bing.com/ttranslatev3?isVertical=1&IG=ABC123&IID=translator.5036.1", False
    xmlHttp.setRequestHeader "Content-Type", "application/x-www-form-urlencoded"
    ' 构造请求体
    xmlHttp.Send "text=" & URLEncode(text) & "&from=&to=en"
    
    response = xmlHttp.responseText
    ' 解析JSON中的detectedLanguage
    jsonStart = InStr(response, """detectedLanguage"":{""language"":""") + 31
    jsonEnd = InStr(jsonStart, response, """")
    DetectLanguage_Bing = Mid(response, jsonStart, jsonEnd - jsonStart)
    
    Set xmlHttp = Nothing
End Function

注意：Bing的接口参数可能会不定期调整，若失效需检查请求参数格式。

内容的提问来源于stack exchange，提问作者Derek