从txt文件中仅读取整数并将每个发现的值相加 [英] Reading only the integers from a txt file and adding the value up for each found

问题描述

我正在尝试读取一个包含整数字符串的txt文件.我希望能够仅从此文件中获取整数并将每个值相加以创建总计.我设法很好地读取了文件，并且能够识别出整数和非整数.我将如何将整数加在一起?

I am trying to read a txt file that contains strings with integers. I would like to be able to get just the integers from this file and add the value each to create a total. I have managed to read the file fine and have been able to identify the ints and non. How would I go about adding the integers together?

public void goalCount() throws FileNotFoundException {

  int goals=0;
  double total=0;

  try {
    Scanner scan = new Scanner(new File("validtest.txt.txt"));

    // find the next int token and print it
    // loop for the whole scanner
    while (scan.hasNext()) {  

      // if the next is a int, print found and the int
      if (scan.hasNextInt()) {
        System.out.println("Found :" + scan.nextInt());
        //goals = scan.nextInt();
        //total+= goals;
      }
      // if no int is found, print "Not Found:" and the token
      System.out.println("Not Found :" + scan.next());
    }

    // close the scanner
    scan.close();

  } catch(Exception e) {

  }
  System.out.println("Total Goals:"+total); //error handling
}

txt文件示例

Leeds United : Liverpool : 1 : 2
Chelsea :  Manchester City : 1 : 1
Aston Villa : Middlesbrough : 3 : 1
Tottenham Hotspur : Stoke City : 0 : 0

推荐答案

您必须原谅我，这种方法行不通.您需要做的是一次读取一行，然后将行按每个空格分开，以获取一组单词.从那里您可以识别整数并存储值.

You'll have to excuse me, that method will not work. What you need to do is read one line at a time, then split the line by each space, to get an array of words. From there you can identify integers and store the value.

final static String filename = "FILENAME.txt";

   public static void main(String[] args) {

      Scanner scan = null;
      File f = new File(filename);
      try {
         scan = new Scanner(f);
      } catch (FileNotFoundException e) {
         System.out.println("File not found.");
         System.exit(0);
      }

      int total = 0;
      boolean foundInts = false; //flag to see if there are any integers

      while (scan.hasNextLine()) { //Note change
         String currentLine = scan.nextLine();
         //split into words
         String words[] = currentLine.split(" ");

         //For each word in the line
         for(String str : words) {
            try {
               int num = Integer.parseInt(str);
               total += num;
               foundInts = true;
               System.out.println("Found: " + num);
            }catch(NumberFormatException nfe) { }; //word is not an integer, do nothing
         }
      } //end while 

      if(!foundInts)
         System.out.println("No numbers found.");
      else
         System.out.println("Total: " + total);

      // close the scanner
      scan.close();
   }

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