如何使用正则表达式检查Aadhar号码是否有效

给定字符串str ，任务是使用正则表达式检查给定的字符串是否为有效的Aadhar编号。有效的Aadhar编号必须满足以下条件：

1. 它应该有12位数字。
2. 它不应以0和1开头。
3. 它不应包含任何字母和特殊字符。
4. 每4位数字后应留有空格。

例子：

Input: str = “3675 9834 6012” 
Output: true 
Explanation: 
The given string satisfies all the above mentioned conditions. Therefore, it is a valid Aadhar number.
Input: str = “3675 9834 6012 8” 
Output: false 
Explanation: 
The given string contains 13 digits. Therefore, it is not a valid Aadhar number. 

方法：想法是使用正则表达式解决此问题。可以按照以下步骤计算答案：

• 获取字符串。
• 创建一个正则表达式以检查有效的Aadhar编号，如下所述：

regex = “^[2-9]{1}[0-9]{3}\\s[0-9]{4}\\s[0-9]{4}$”;

• 在哪里：
  • ^表示字符串的开头。
  • [2-9] {1}表示第一位数字应为2-9中的任何数字。
  • [0-9] {3}表示第一个数字应该是0-9之间的任何数字之后的后3个数字。
  • \\ s表示空格。
  • [0-9] {4}表示接下来的4位数字应为0-9。
  • \\ s表示空格。
  • [0-9] {4}表示接下来的4位数字应为0-9。
  • $表示字符串的结尾。
• 将给定的字符串与正则表达式匹配。在Java，这可以通过使用Pattern.matcher()来完成。
• 如果字符串与给定的正则表达式匹配，则返回true；否则返回false。

下面是上述方法的实现：

C++

// C++ program to validate the
// Aadhar number using Regular Expression
#include 
#include 
using namespace std;
 
// Function to validate the Aadhar number.
bool isValidAadharNumber(string str)
{
 
  // Regex to check valid Aadhar number.
  const regex pattern("^[2-9]{1}[0-9]{3}\\s[0-9]{4}\\s[0-9]{4}$");
 
  // If the Aadhar number
  // is empty return false
  if (str.empty())
  {
     return false;
  }
 
  // Return true if the Aadhar number
  // matched the ReGex
  if(regex_match(str, pattern))
  {
    return true;
  }
  else
  {
    return false;
  }
}
 
// Driver Code
int main()
{
  // Test Case 1:
  string str1 = "3675 9834 6015";
  cout << isValidAadharNumber(str1) << endl;
 
  // Test Case 2:
  string str2 = "4675 9834 6012 8";
  cout << isValidAadharNumber(str2) << endl;
 
  // Test Case 3:
  string str3 = "0175 9834 6012";
  cout << isValidAadharNumber(str3) << endl;
 
  // Test Case 4:
  string str4 = "3675 98AF 60#2";
  cout << isValidAadharNumber(str4) << endl;
 
  // Test Case 5:
  string str5 = "417598346012";
  cout << isValidAadharNumber(str5) << endl;
  return 0;
}
 
// This code is contributed by yuvraj_chandra

Java

// Java program to check valid
// Aadhar number using regex.
 
import java.util.regex.*;
class GFG {
 
    // Function to validate Aadhar number.
    public static boolean
    isValidAadharNumber(String str)
    {
        // Regex to check valid Aadhar number.
        String regex
            = "^[2-9]{1}[0-9]{3}\\s[0-9]{4}\\s[0-9]{4}$";
 
        // Compile the ReGex
        Pattern p = Pattern.compile(regex);
 
        // If the string is empty
        // return false
        if (str == null) {
            return false;
        }
 
        // Pattern class contains matcher() method
        // to find matching between given string
        // and regular expression.
        Matcher m = p.matcher(str);
 
        // Return if the string
        // matched the ReGex
        return m.matches();
    }
 
    // Driver Code.
    public static void main(String args[])
    {
 
        // Test Case 1:
        String str1 = "3675 9834 6015";
        System.out.println(isValidAadharNumber(str1));
 
        // Test Case 2:
        String str2 = "4675 9834 6012 8";
        System.out.println(isValidAadharNumber(str2));
 
        // Test Case 3:
        String str3 = "0175 9834 6012";
        System.out.println(isValidAadharNumber(str3));
 
        // Test Case 4:
        String str4 = "3675 98AF 60#2";
        System.out.println(isValidAadharNumber(str4));
 
        // Test Case 5:
        String str5 = "417598346012";
        System.out.println(isValidAadharNumber(str5));
    }
}

Python3

# Python3 program to validate
# Aadhar number using regex.
import re
 
# Function to validate Aadhar
# number.
def isValidAadharNumber(str):
 
    # Regex to check valid
    # Aadhar number.
    regex = ("^[2-9]{1}[0-9]{3}\\" +
             "s[0-9]{4}\\s[0-9]{4}$")
     
    # Compile the ReGex
    p = re.compile(regex)
 
    # If the string is empty
    # return false
    if (str == None):
        return False
 
    # Return if the string
    # matched the ReGex
    if(re.search(p, str)):
        return True
    else:
        return False
 
# Driver code
 
# Test Case 1:
str1 = "3675 9834 6015"
print(isValidAadharNumber(str1))
 
# Test Case 2:
str2 = "4675 9834 6012 8"
print(isValidAadharNumber(str2))
 
# Test Case 3:
str3 = "0175 9834 6012"
print(isValidAadharNumber(str3))
 
# Test Case 4:
str4 = "3675 98AF 60#2"
print(isValidAadharNumber(str4))
 
# Test Case 5:
str5 = "417598346012"
print(isValidAadharNumber(str5))
 
# This code is contributed by avanitrachhadiya2155

输出：

true
false
false
false
false