Question

所以在我的代码中，我正在尝试读取类似的文件：

100
22
123;22
123 342;432

但输出时会包含＆＃34 ;;＆＃34; （例如，100,22,123; 22,123,342; 432}）。我试图将文件变成一个数组（例如{100,22,123,22,123 ...}）。有没有办法读取文件，但忽略分号？谢谢！

    public static void main(String args [])
{
    String[] inFile = readFiles("ElevatorConfig.txt");
    for ( int i = 0; i <inFile.length; i = i + 1)
    {
        System.out.println(inFile[i]);
    }
    System.out.println(Arrays.toString(inFile));
}
public static String[] readFiles(String file)
{
    int ctr = 0;
    try{
        Scanner s1 = new Scanner(new File(file));
        while (s1.hasNextLine()){
            ctr = ctr + 1;
            s1.next();

        }
        String[] words = new String[ctr];
        Scanner s2 = new Scanner(new File(file));
        for ( int i = 0 ; i < ctr ; i = i + 1){
            words[i] = s2.next();


        }
        return words;
    }
    catch(FileNotFoundException e)
    {
        return null;
    }

}

Answer 1

    public static String[] readFiles(String file)
{
    int ctr = 0;
    try{
        Scanner s1 = new Scanner(new File(file));
        while (s1.hasNextLine()){
            ctr = ctr + 1;
            s1.next();

        }
        String[] words = new String[ctr];
        Scanner s2 = new Scanner(new File(file));
        for ( int i = 0 ; i < ctr ; i = i + 1){
            words[i] = s2.next();


        }
        return words;
    }
    catch(FileNotFoundException e)
    {
        return null;
    }

}

将其替换为

public static String [] readFiles（String file）{

 List<String> retList = new ArrayList<String>();
  Scanner s2 = new Scanner(new File(file));
    for ( int i = 0 ; i < ctr ; i = i + 1){
         String temp = s2.next();
         String[] tempArr = se.split(";");
         for(int k=0;k<tempArr.length;k++) {
             retList.add(tempArr[k]);

         }
}

return (String[]) retList.toArray();

}

Answer 2

使用正则表达式。将整个文件读入String （将每个标记作为字符串读取，并在字符串中的每个标记后面附加空格），然后将其拆分为空格和半冒号。

String x <--- contains all contents of the file
String[] words = x.split("[\\s\\;]+");

words[]的内容是：

"100", "22", "123", "22", "123", "342", "432"

在使用数字之前，请务必将它们解析为int。

Answer 3

使用BufferedReader的简单方法逐行读取然后拆分;

public static String[] readFiles(String file)
{
BufferedReader br = new BufferedReader(new FileReader(file))) 
StringBuilder sb = new StringBuilder();
String line = br.readLine();
while (line != null) {
    sb.append(line);
    sb.append(System.lineSeparator());
    line = br.readLine();
}
 String allfilestring = sb.toString();
 String[]  array = allfilestring.split(";");

return array;
 }

Answer 4

您可以使用<?php $con=mysqli_connect("localhost","root","mypassword","myDB"); // Check connection if (mysqli_connect_errno()) { echo "Failed to connect to MySQL: " . mysqli_connect_error(); } echo "<h3 style='color: darkgreen;'> Connected to database. </h3> <br />"; $result = mysqli_query($con,"SELECT * FROM Inventory"); echo "<table border='1'> <tr> <th>Item ID</th> <th>Item Name</th> </tr>"; while($row = mysqli_fetch_array($result)) { echo "<tr>"; echo "<td class='item-id'>" . $row['itemID'] . "</td>"; echo "<td class='item-name'>" . $row['itemName'] . "</td>"; echo "</tr>"; } echo "</table>"; mysqli_close($con); ?> <script src="https://code.jquery.com/jquery-1.12.4.min.js" integrity="sha256-ZosEbRLbNQzLpnKIkEdrPv7lOy9C27hHQ+Xp8a4MxAQ=" crossorigin="anonymous"></script> <script type="text/javascript"> $("tr").click(function() { var id = $(this).find('.item-id').text(); var name = $(this).find('.item-name').text(); alert("Your data is: " + $.trim(id) + " , " + $.trim(name)); }); </script>根据您的要求使用正则表达式将字符串拆分为数组。

split()

希望有所帮助

Answer 5

保留用于计算数组大小的代码。我只想改变你输入你的价值观的方式。

    for (int i = 0; i < ctr; i++) {
       words[i] = "" + s1.nextInt();
    }

Answer 6

另一个选项是用空格替换整个文件字符串中的所有非数字字符。这样就可以忽略任何非数字字符。

BufferedReader br = new BufferedReader(new FileReader(file))) 
StringBuilder sb = new StringBuilder();
String line = br.readLine();
while (line != null) {
    sb.append(line);
    line = br.readLine();
}

String str = sb.toString();
str = str.replaceAll("\\D+"," ");

现在你有一个字符串，数字用空格分隔，我们可以将它们标记为数字字符串。

String[] final = str.split("\\s+");

然后转换为int数据类型。

如何从用冒号分隔的文件中读取整数？

6 个答案: