無法將數組傳遞給方法

Question

爲什麼我無法將appleArray，blueberryArray和peanutArray發送到calcTotalPies方法？

final int MAX_PIES = 81; 
final int MAX_PER_TYPE = 27; 

String typeOfPie = getPieType(); 
while (!typeOfPie.equalsIgnoreCase("q")) { 
    if (typeOfPie.equalsIgnoreCase("apple")) { 
     String[] appleArray = fillApple(typeOfPie, MAX_PER_TYPE); 
    } 
    else if (typeOfPie.equalsIgnoreCase("blueberry")) { 
     String[] blueberryArray = fillBlueberry(typeOfPie, MAX_PER_TYPE); 
    } 
    else if (typeOfPie.equalsIgnoreCase("peanut")) { 
     String[] peanutArray = fillPeanut(typeOfPie, MAX_PER_TYPE); 
    } 
    typeOfPie = getPieType(); 
} 

if (typeOfPie.equalsIgnoreCase("q")) { 
     int totalPies = calcTotalPies(appleArray, blueberryArray, peanutArray); 
} 

Answer 1

當你的代碼執行到達你的方法時，如果else塊聲明內部的while循環，你的數組聲明已經結束並且它們不可訪問。所以你需要在循環之外初始化它們。

試試這個

final int MAX_PIES = 81; 
final int MAX_PER_TYPE = 27; 

String[] peanutArray = null; 
String[] blueberryArray = null; 
String[] appleArray = null; 

String typeOfPie = getPieType(); 
while (!typeOfPie.equalsIgnoreCase("q")) { 
    if (typeOfPie.equalsIgnoreCase("apple")) { 
     appleArray = fillApple(typeOfPie, MAX_PER_TYPE); 
    } else if (typeOfPie.equalsIgnoreCase("blueberry")) { 
     blueberryArray = fillBlueberry(typeOfPie, MAX_PER_TYPE); 
    } else if (typeOfPie.equalsIgnoreCase("peanut")) { 
     peanutArray = fillPeanut(typeOfPie, MAX_PER_TYPE); 
    } 
    typeOfPie = getPieType(); 
} 

if (typeOfPie.equalsIgnoreCase("q")) { 
    int totalPies = calcTotalPies(appleArray, blueberryArray, peanutArray); 
} 

Answer 2

局部變量總是一個塊中聲明和僅在該塊（注意：方法體或if的主體或一個環也是一個塊）活着。

你宣佈appleArray，只在其周圍if -blocks blueberryArray和peanutArray，因此他們不是在最低if - 塊活着。編譯器應該告訴你一些這些數組沒有被定義。