Java 读取由分隔符分隔的文件内容
约翰,100.00200.00 如何读取文本文件的内容,然后在引号下打印字符串 输出应该是 Jhon 100.00 200.00Java 读取由分隔符分隔的文件内容,java,regex,Java,Regex,约翰,100.00200.00 如何读取文本文件的内容,然后在引号下打印字符串 输出应该是 Jhon 100.00 200.00 String CUSTOMER, CURRENT, NEW; Scanner sc = new Scanner(str); sc.useDelimiter(","); while(sc.hasNext()){ CUSTOMER = sc.next(); CURRENT = sc.next(); N
String CUSTOMER, CURRENT, NEW;
Scanner sc = new Scanner(str);
sc.useDelimiter(",");
while(sc.hasNext()){
CUSTOMER = sc.next();
CURRENT = sc.next();
NEW = sc.next();
System.out.println("" + CUSTOMER + " " + CURRENT +
" " + NEW);
}
sc.close();
如何将标记与引号分开。我得到的上述代码的输出如下
Jhon 100.00 200.00您可以通过以下方式获得所需的输出:
String CUSTOMER, CURRENT, NEW;
Scanner sc = new Scanner(str);
sc.useDelimiter(",");
while(sc.hasNext()){
CUSTOMER = sc.next();
CURRENT = sc.next();
NEW = sc.next();
System.out.println("" + CUSTOMER + " " + CURRENT +
" " + NEW);
}
sc.close();
public static void main(String[] args) {
Pattern p = Pattern.compile(".*?\\\"(.*?)\\\".*?");
Matcher m = p.matcher("\"John\",\"100.00\",\"200.00\"");
while (m.find()) {
System.out.println(m.group(1));
}
}
说明
输出
扫描器也可以使用除空白以外的分隔符。此示例从字符串中读取多个项目:
String input = "1 fish 2 fish red fish blue fish";
Scanner s = new Scanner(input).useDelimiter("\\s*fish\\s*");
所以,您可以通过子字符串1、len-1和useDelimiter \、\避免第一个和最后一个引号,中间部分使用3个符号delim
String str = "\"John\",\"100.00\",\"200.00\"";
System.out.println(str);
String CUSTOMER, CURRENT, NEW;
Scanner sc = new Scanner(
str.substring(1,str.length()-1) // <--- here substring
);
sc.useDelimiter("\",\""); // <---- here your split: <token>","<token>
while(sc.hasNext()){
CUSTOMER = sc.next();
CURRENT = sc.next();
NEW = sc.next();
System.out.println("" + CUSTOMER + " " + CURRENT + " " + NEW);
}
sc.close();
以下是完成任务的另一种方法:
String line, customerName, currentVal, newVal;
try (Scanner sc = new Scanner(new File("salesrep.txt"))) {
while (sc.hasNextLine()) {
line = sc.nextLine().replace("\"", "");
//skip blank lines (if any)
if (line.equals("")) {
continue;
}
String[] lineData = line.split(",");
customerName = lineData[0];
currentVal = lineData[1]; // or: double currentVal = Double.parseDouble(lineData[1]);
newVal = lineData[2]; // or: double newVal = Double.parseDouble(lineData[2]);
System.out.println("" + customerName + " " + currentVal + " " + newVal);
}
}
catch (FileNotFoundException ex) {
ex.printStackTrace();
}
您忘记发布您迄今为止尝试过的代码。您迄今为止尝试过什么吗??与我们分享。这看起来像CSV数据,所以使用CSV解析器!!!!我从一个文件中获取信息,因此如何使其在文件输入中工作您可以通过
String line, customerName, currentVal, newVal;
try (Scanner sc = new Scanner(new File("salesrep.txt"))) {
while (sc.hasNextLine()) {
line = sc.nextLine().replace("\"", "");
//skip blank lines (if any)
if (line.equals("")) {
continue;
}
String[] lineData = line.split(",");
customerName = lineData[0];
currentVal = lineData[1]; // or: double currentVal = Double.parseDouble(lineData[1]);
newVal = lineData[2]; // or: double newVal = Double.parseDouble(lineData[2]);
System.out.println("" + customerName + " " + currentVal + " " + newVal);
}
}
catch (FileNotFoundException ex) {
ex.printStackTrace();
}