正则表达式教程：英文姓名解析

一、正则解释

正则表达式 /(^[a-zA-Z][a-zA-Z\s]{0,20}[a-zA-Z]$)/ 分为以下部分：

• ^: 表示字符串的开始。
• [a-zA-Z]: 匹配一个字母，可以是小写或大写。
• [a-zA-Z\s]{0,20}: 匹配由字母和空格组成的字符串，长度在 0 到 20 之间（不包括）。
• [a-zA-Z]: 匹配一个字母，可以是小写或大写。
• $: 表示字符串的结束。

二、使用场景

此正则表达式用于匹配英文姓名，它可以用于：

• 从文本中提取英文姓名
• 验证用户输入的姓名是否为英文格式
• 对姓名进行格式化或处理

三、代码示例

JavaScript

const regex = /(^[a-zA-Z][a-zA-Z\s]{0,20}[a-zA-Z]$)/;
const names = ['James', 'Kevin Wayne Durant', 'Dirk Nowitzki'];

for (let name of names) {
  if (regex.test(name)) {
    console.log(`${name} is a valid English name.`);
  } else {
    console.log(`${name} is not a valid English name.`);
  }
}

Java

import java.util.regex.Pattern;

public class EnglishNameValidation {

  public static void main(String[] args) {
    String regex = "^[a-zA-Z][a-zA-Z\\s]{0,20}[a-zA-Z]
import java.util.regex.Pattern;

public class EnglishNameValidation {

  public static void main(String[] args) {
    String regex = "^[a-zA-Z][a-zA-Z\\s]{0,20}[a-zA-Z]$";
    String[] names = {"James", "Kevin Wayne Durant", "Dirk Nowitzki"};

    for (String name : names) {
      boolean isValid = Pattern.matches(regex, name);
      System.out.println(name + " is " + (isValid ? "valid" : "invalid") + " English name.");
    }
  }
}
quot;;
    String[] names = {"James", "Kevin Wayne Durant", "Dirk Nowitzki"};

    for (String name : names) {
      boolean isValid = Pattern.matches(regex, name);
      System.out.println(name + " is " + (isValid ? "valid" : "invalid") + " English name.");
    }
  }
}

PHP

<?php

$regex = '/^[a-zA-Z][a-zA-Z\s]{0,20}[a-zA-Z]$/';
$names = ['James', 'Kevin Wayne Durant', 'Dirk Nowitzki'];

foreach ($names as $name) {
  if (preg_match($regex, $name)) {
    echo "$name is a valid English name.<br>";
  } else {
    echo "$name is not a valid English name.<br>";
  }
}

Python

import re

regex = r"^[a-zA-Z][a-zA-Z\s]{0,20}[a-zA-Z]
import re

regex = r"^[a-zA-Z][a-zA-Z\s]{0,20}[a-zA-Z]$"
names = ['James', 'Kevin Wayne Durant', 'Dirk Nowitzki']

for name in names:
  if re.match(regex, name):
    print(f"{name} is a valid English name.")
  else:
    print(f"{name} is not a valid English name.")
quot;
names = ['James', 'Kevin Wayne Durant', 'Dirk Nowitzki']

for name in names:
  if re.match(regex, name):
    print(f"{name} is a valid English name.")
  else:
    print(f"{name} is not a valid English name.")