List.Map <String，String>

Question

如何將Map.Entry<String, String>的列表轉換爲String？

List<Map.Entry<String, String>> : [AREA_DS_ID=1,5,9,13,17,21,25,29,33, PROJECTS_ID=13,78,267,18,28,33,55,99, SIGNAL_NAME=a, ASSESSMENTNAME=a] 
// these are the values which I need to convert into String. 

Answer 1

這是什麼意思？你想將地圖元素（鍵=值）轉換爲字符串值？對於這一點，你可以使用地圖條目集循環和讀取鍵和地圖元素的值，並創建自定義字符串和CONCAT所有的列表：

String resultString ="" ; 
for(Map.Entry<String,String> entry : map.EntrySet()) 
{ 
    String key = entry.getKey(); 
    String value = entry.getValue(); 
    // create custom string for each map element 
    String testString = key + "=" + value; 
    resultString += testString ; 
} 

的地圖列表，你可以在列表定義循環：

for(Map<String,String> map : list) 
{ 
    // use map such above code 
    ... 
} 

Answer 2

就像一個回答您的評論：我剛剛試了一下，也沒有例外可言：

Map<String, String> map = new LinkedHashMap<>(); 
map.put("AREA_DS_ID", "1,5,9,13,17,21,25,29,33"); 
map.put("PROJECTS_ID", "13,78,267,18,28,33,55,99"); 
map.put("SIGNAL_NAME", "a"); 
map.put("ASSESSMENTNAME", "a"); 

List<String> entryList = new ArrayList<>(); 
StringBuilder sb = new StringBuilder(); 
for (Entry<String, String> entry : map.entrySet()) { 
    String value = entry.getKey() + '=' + entry.getValue(); 
    entryList.add(value); 
    sb.append(value); 
} 
String[] entries = entryList.toArray(new String[entryList.size()]); 
String mapAsString = sb.toString();