Question

我想将字符串与hashmap中的键进行比较。我尝试使用此处提到的步骤Compare map key with a list of strings，但对我不起作用。

hashmap包含许多条目，并希望比较我传递的字符串。如果键匹配字符串，它应该停在那里并打印匹配字符串的值。以下是我的代码：

HashMap<String, MyBO> myObjs = MyData.getMyData();
Set<String> keys = myObjs.keySet();
String  id = "ABC";
for(String code: keys) {
    MyBO bo  = myObjs.get(code);
    if(keys.contains(itemId)) {
        System.out.println("Matched key = " + id);
    } else {
        System.out.println("Key not matched with ID");
    }
}

Answer 1

这对你有用

    HashMap<String, MyBO> myObjs = MyData.getMyData();
    String  id = "ABC";
    if(myObjs.containsKey(id)){
        System.out.println("Matched key = " + id);
    } else{
        System.out.println("Key not matched with ID");
    }

例如，请考虑以下示例

    HashMap<String, String> myObjs =new HashMap<>();
    myObjs.put("ABC","a");
    myObjs.put("AC","a");
    String  id = "ABC";
    if(myObjs.containsKey(id)){
        System.out.println("Matched key = " + id);
    } else{
        System.out.println("Key not matched with ID");
    }

Out put。

    Matched key = ABC

Answer 2

尝试使用此代码并将其与您的代码要求相似，它将适用于您

for (String key:keys){
            String value = mapOfStrings.get(key);
            //here it must uderstand, that the inputText contains "java" that equals to
            //the key="java" and put in outputText the correspondent value
            if (inputText.contains(key))
            {
               outputText = value;
            }
        }

Answer 3

以下是您要找的内容，请注意与您的代码的不同之处：

HashMap<String, MyBO> myObjs = MyData.getMyData();
Set<String> keys = myObjs.keySet();
String  id = "ABC";
for(String code: keys) {
    if(code.equals(id) { /* this compares the string of the key to "ABC" */
        System.out.println("Matched key = " + id);
    } else {
        System.out.println("Key not matched with ID");
    }
}

或者，您可以这样做：

HashMap<String, MyBO> myObjs = MyData.getMyData();
Set<String> keys = myObjs.keySet();
if(keys.contains("ABC") { /* this checks the set for the value "ABC" */
    System.out.println("Matched key = ABC");
 } else {
    System.out.println("Key not matched with ID");
 }
}

Answer 4

试试这种方式，

HashMap<String, String> dataArr = new HashMap<>();
        dataArr.put("Key 1", "First String");
        String keyValueStr = dataArr.keySet().toString();
        String matchValueStr = "Key 1";
        //System.out.println(keyValueStr);
        if(keyValueStr.equals("["+matchValueStr+"]"))
            System.out.println("Match Found");
        else
            System.out.println("No Match Found");

将哈希映射键与字符串进行比较

4 个答案: