java中String數組和List的互相轉化

List轉String數組

方法一

//先准備一個List
List testList=new ArrayList<>();
testList.add("a");
testList.add("b");
testList.add("c");
//List轉String
String[] strs1=testList.toArray(new String[testList.size()]);
for(String s:strs1){
   System.out.println(s);
}

方法二

//先准備一個List
List testList=new ArrayList<>();
testList.add("a");
testList.add("b");
testList.add("c");
//List轉String
String[] strs2 = new String[testList.size()];
for(int i=0;i<testList.size();i++){
   strs2[i]=testList.get(i);
}
for(String s:strs2){
  System.out.println(s);
}

String數據轉List

方法一

//准備一個String數組
String[] strs = {"aa","bb","cc"};
//String數組轉List
List strsToList1= Arrays.asList(strs);
for(String s:strsToList1){
 System.out.println(s);
}

方法二

//准備一個String數組
String[] strs = {"aa","bb","cc"};
//String數組轉List
List strsToList2=new ArrayList<>();
Collections.addAll(strsToList2,strs);
for(String s:strsToList2){
   System.out.println(s);
}

方法三

//准備一個String數組
String[] strs = {"aa","bb","cc"};
//String數組轉List
List strsToList3=new ArrayList<>();
for(String s:strs){
    strsToList3.add(s);
}
for(String s:strsToList3){
    System.out.println(s);
}