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Whichdeterminesif“prefs”isadirectoryandexistsonthefilesystem?()A.Booleanexists=Directory.exists（“prefs”）；B.Booleanexists=（newFile（“prefs”））.isDir（）；C.Booleanexists=（newDirectory（“prefs”））.exists（）；D.Booleanexists=（newFile（“prefs”））.isDirectory（）；E.Boolean

题目
Whichdeterminesif“prefs”isadirectoryandexistsonthefilesystem?()

A.Booleanexists=Directory.exists（“prefs”）；

B.Booleanexists=（newFile（“prefs”））.isDir（）；

C.Booleanexists=（newDirectory（“prefs”））.exists（）；

D.Booleanexists=（newFile（“prefs”））.isDirectory（）；

E.Booleanexists=true；Try{Directoryd=newDirectory（“prefs”）；} catch（FileNotFoundExceptione）{exists=false；}

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1.SharedPreferences保存文件的路径和扩展名是()。A./data/data/shared_prefs/*.txtB./data/data/package name/shared_prefs/*.xmlC./mnt/sdcard/指定文件夹指定扩展名D.任意路径指定扩展名

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