如何使用Scanner类从控制台读取输入?就像这样:
System.out.println("Enter your username: ");
Scanner = input(); // Or something like this, I don't know the code
基本上,我想要的只是让扫描器读取用户名的输入,并将输入分配给一个String变量。
如何使用Scanner类从控制台读取输入?就像这样:
System.out.println("Enter your username: ");
Scanner = input(); // Or something like this, I don't know the code
基本上,我想要的只是让扫描器读取用户名的输入,并将输入分配给一个String变量。
当前回答
input.nextInt()方法有问题——它只读取int值。
因此,当使用input.nextLine()读取下一行时,您会收到“\n”,即回车键。所以要跳过这个,你必须添加input.nextLine()。
试着这样做:
System.out.print("Insert a number: ");
int number = input.nextInt();
input.nextLine(); // This line you have to add (it consumes the \n character)
System.out.print("Text1: ");
String text1 = input.nextLine();
System.out.print("Text2: ");
String text2 = input.nextLine();
其他回答
import java.util.Scanner; // Import the Scanner class
class Main { // Main is the class name
public static void main(String[] args) {
Scanner myObj = new Scanner(System.in); // Create a Scanner object
System.out.println("Enter username");
String userName = myObj.nextLine(); // Read user input
System.out.println("Username is: " + userName); // Output user input
}
}
Scanner scan = new Scanner(System.in);
String myLine = scan.nextLine();
说明java.util.Scanner如何工作的一个简单示例是从System.in中读取单个整数。这真的很简单。
Scanner sc = new Scanner(System.in);
int i = sc.nextInt();
要检索用户名,我可能会使用sc.nextLine()。
System.out.println("Enter your username: ");
Scanner scanner = new Scanner(System.in);
String username = scanner.nextLine();
System.out.println("Your username is " + username);
如果您想对输入进行更多控制,或者只是验证用户名变量,也可以使用next(字符串模式)。
你可以在java.util.Scanner的API文档中找到更多关于它们实现的信息
当用户输入他/她的用户名时,也检查是否有有效的输入。
java.util.Scanner input = new java.util.Scanner(System.in);
String userName;
final int validLength = 6; // This is the valid length of an user name
System.out.print("Please enter the username: ");
userName = input.nextLine();
while(userName.length() < validLength) {
// If the user enters less than validLength characters
// ask for entering again
System.out.println(
"\nUsername needs to be " + validLength + " character long");
System.out.print("\nPlease enter the username again: ");
userName = input.nextLine();
}
System.out.println("Username is: " + userName);
import java.util.*;
class Ss
{
int id, salary;
String name;
void Ss(int id, int salary, String name)
{
this.id = id;
this.salary = salary;
this.name = name;
}
void display()
{
System.out.println("The id of employee:" + id);
System.out.println("The name of employye:" + name);
System.out.println("The salary of employee:" + salary);
}
}
class employee
{
public static void main(String args[])
{
Scanner sc = new Scanner(System.in);
Ss s = new Ss(sc.nextInt(), sc.nextInt(), sc.nextLine());
s.display();
}
}