你可以使用 ML Kit 辨識文字字串的語言。您可以查看字串最可能的語言,以及所有字串所有可用語言的可信度分數。
ML Kit 可辨識原生指令碼中超過 100 種語言的文字。此外,系統也可以辨識阿拉伯文、保加利亞文、中文、希臘文、北印度文、日文和俄文。查看支援語言和指令碼的完整清單。
立即體驗
- 使用範例應用程式,查看這個 API 的使用範例。
事前準備
- 在 Podfile 中加入下列 ML Kit pod:
pod 'GoogleMLKit/LanguageID', '3.2.0'
- 安裝或更新專案的 Pod 後,請使用其
.xcworkspace
開啟 Xcode 專案。Xcode 12.4 以上版本支援 ML Kit。
辨別字串的語言
如要識別字串的語言,請取得 LanguageIdentification
的執行個體,然後將字串傳遞至 identifyLanguage(for:)
方法。
例如:
Swift
let languageId = NaturalLanguage.languageIdentification() languageId.identifyLanguage(for: text) { (languageCode, error) in if let error = error { print("Failed with error: \(error)") return } if let languageCode = languageCode, languageCode != "und" { print("Identified Language: \(languageCode)") } else { print("No language was identified") } }
Objective-C
MLKLanguageIdentification *languageId = [MLKLanguageIdentification languageIdentification]; [languageId identifyLanguageForText:text completion:^(NSString * _Nullable languageCode, NSError * _Nullable error) { if (error != nil) { NSLog(@"Failed with error: %@", error.localizedDescription); return; } if (![languageCode isEqualToString:@"und"] ) { NSLog(@"Identified Language: %@", languageCode); } else { NSLog(@"No language was identified"); } }];
如果呼叫成功,系統會將 BCP-47 語言代碼傳遞給完成處理常式,用來表示文字的語言。如果可以順利偵測到語言,則會傳遞 und
(未判定) 程式碼。
根據預設,ML Kit 預設只會在確認具可信度值至少為 0.5 的語言時,傳回非 und
值。如要變更這個門檻,請將 LanguageIdentificationOptions
物件傳遞至 languageIdentification(options:)
:
Swift
let options = LanguageIdentificationOptions(confidenceThreshold: 0.4) let languageId = NaturalLanguage.languageIdentification(options: options)
Objective-C
MLKLanguageIdentificationOptions *options = [[MLKLanguageIdentificationOptions alloc] initWithConfidenceThreshold:0.4]; MLKLanguageIdentification *languageId = [MLKLanguageIdentification languageIdentificationWithOptions:options];
取得字串可能的語言
如要取得字串最可能語言的可信度值,請取得 LanguageIdentification
的執行個體,然後將字串傳遞至 identifyPossibleLanguages(for:)
方法。
例如:
Swift
let languageId = NaturalLanguage.languageIdentification() languageId.identifyPossibleLanguages(for: text) { (identifiedLanguages, error) in if let error = error { print("Failed with error: \(error)") return } guard let identifiedLanguages = identifiedLanguages, !identifiedLanguages.isEmpty, identifiedLanguages[0].languageCode != "und" else { print("No language was identified") return } print("Identified Languages:\n" + identifiedLanguages.map { String(format: "(%@, %.2f)", $0.languageCode, $0.confidence) }.joined(separator: "\n")) }
Objective-C
MLKLanguageIdentification *languageId = [MLKLanguageIdentification languageIdentification]; [languageId identifyPossibleLanguagesForText:text completion:^(NSArray* _Nonnull identifiedLanguages, NSError * _Nullable error) { if (error != nil) { NSLog(@"Failed with error: %@", error.localizedDescription); return; } if (identifiedLanguages.count == 1 && [identifiedLanguages[0].languageCode isEqualToString:@"und"] ) { NSLog(@"No language was identified"); return; } NSMutableString *outputText = [NSMutableString stringWithFormat:@"Identified Languages:"]; for (MLKIdentifiedLanguage *language in identifiedLanguages) { [outputText appendFormat:@"\n(%@, %.2f)", language.languageCode, language.confidence]; } NSLog(outputText); }];
如果呼叫成功,系統會將 IdentifiedLanguage
物件清單傳遞至接續處理常式。您可以從每個物件取得語言的 BCP-47 程式碼,並確保字串以該語言顯示。請注意,這些值代表整個字串採用指定語言的信賴度,而 ML Kit 不會在單一字串中識別多種語言。
根據預設,ML Kit 只會傳回可信度值至少為 0.01 的語言。如要變更這個門檻,請將 LanguageIdentificationOptions
物件傳遞至 languageIdentification(options:)
:
Swift
let options = LanguageIdentificationOptions(confidenceThreshold: 0.4) let languageId = NaturalLanguage.languageIdentification(options: options)
Objective-C
MLKLanguageIdentificationOptions *options = [[MLKLanguageIdentificationOptions alloc] initWithConfidenceThreshold:0.4]; MLKLanguageIdentification *languageId = [MLKLanguageIdentification languageIdentificationWithOptions:options];
如果沒有語言符合此門檻,清單中會有一個項目,值為 und
。