如何从txt文件中获取“ =”符号后的数据？

Question

I have a program, in Java, that will save data to a .txt file and save it like:

intdata=2

stringdata=hello

How will I read the data from the text file and specify the value I need. Lets say I want the intdata value, it would return the part after the equals. How do I only return the part after the equals?

Answer 1

If you don't care about the key it's attached to: use String.split .

Scanner scan = new Scanner(new File("file.txt"));
String value = scan.nextLine().split("=")[1];

If you do care about the key it's attached to: use String.split in conjunction with a Map .

Scanner scan = new Scanner(new File("file.txt"));
Map<String, String> values = new HashMap<>();
while(scan.hasNextLine()) {
    String[] line = scan.nextLine().split("=");
    values.put(line[0], line[1]);
}

Alternatively, if it's a proper .properties file, you could elect to use Properties instead:

Properties propertiesFile = new Properties();
propertiesFile.load(new FileInputStream("file.txt"));

// use it like a regular Properties object now.