如何比较字符串到枚举类型在Java？ [英] How to compare string to enum type in Java?

问题描述

我有一个美国所有州的枚举列表如下：

  public enum State 
 { AL，AK，AZ，AR，...，WY} 
  

将从包含状态的文本文件读取输入。因为它们是字符串，我如何将它与枚举列表的值进行比较，以便为我设置的变量赋值：

 私有状态; 
  

我理解我需要浏览枚举列表。但是，由于值不是字符串类型，你怎么比较呢？这是我只是盲目地输出。我不知道是否正确。

  public void setState（String s）
 {
 for（State st：State.values（））
 {
 if（s == State.values（）。toString（））
 {
s = State.valueOf ）; 
 break; 
} 
} 
} 
  

解决方案>

尝试此

  public void setState（String s）{
 state = State.valueOf（s） ; 
} 
  

您可能想要处理IllegalArgumentException，不符合任何状态

I have an enum list of all the states in the US as following:

public enum State
{ AL, AK, AZ, AR, ..., WY }

and in my test file, I will read input from a text file that contain the state. Since they are string, how can I compare it to the value of enum list in order to assign value to the variable that I have set up as:

private State state;

I understand that I need to go through the enum list. However, since the values are not string type, how can you compare it? This is what I just type out blindly. I don't know if it's correct or not.

public void setState(String s)
{
    for (State st : State.values())
    {
        if (s == State.values().toString())
        {
           s = State.valueOf();
           break;
        }
    }
}

解决方案

try this

public void setState(String s){
 state = State.valueOf(s);
}

You might want to handle the IllegalArgumentException that may be thrown if "s" value doesn't match any "State"

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