Java Character isLetterOrDigit()与实例

java.lang.Character.isLetterOrDigit(char ch) 是java中的一个内置方法，用于确定指定字符是字母还是数字。

语法

public static boolean isLetterOrDigit(char ch)

参数： 该函数接受一个强制参数 ch ，表示要测试的字符。

返回值： 该函数返回一个布尔值。如果该字符是一个字母或数字，则布尔值为真，否则为假。

以下程序说明了上述方法。

程序1 :

// Java program to illustrate the
// Character.isLetterOrDigit() method
  
import java.lang.*;
  
public class GFG {
  
    public static void main(String[] args)
    {
  
        // two characters
        char c1 = 'Z', c2 = '2';
  
        // Function to check if the character is letter or digit
        boolean bool1 = Character.isLetterOrDigit(c1);
        System.out.println(c1 + " is a letter/digit ? " + bool1);
  
        // Function to check if the character is letter or digit
        boolean bool2 = Character.isLetterOrDigit(c2);
        System.out.println(c2 + " is a letter/digit ? " + bool2);
    }
}

输出:

Z is a letter/digit ? true
2 is a letter/digit ? true

程序2

// Java program to illustrate the
// Character.isLetterOrDigit() method
  
import java.lang.*;
  
public class GFG {
  
    public static void main(String[] args)
    {
  
        // assign character
        char c1 = 'D', c2 = '/';
  
        // Function to check if the character is letter or digit
        boolean bool1 = Character.isLetterOrDigit(c1);
        System.out.println(c1 + " is a letter/digit ? " + bool1);
  
        // Function to check if the character is letter or digit
        boolean bool2 = Character.isLetterOrDigit(c2);
        System.out.println(c2 + " is a letter/digit ? " + bool2);
    }
}

输出:

D is a letter/digit ? true
/ is a letter/digit ? false

**参考资料: **https://docs.oracle.com/javase/7/docs/api/java/lang/Character.html#isLetterOrDigit(char)