AES密钥长度和块长度在不同的编程语言中可能有不同的实现方式。下面是一些常用编程语言中的示例代码：

1. Python：

from Crypto.Cipher import AES

key = b'0123456789abcdef'  # 16字节的密钥
block_size = AES.block_size  # 获取AES的块长度

# 加密
cipher = AES.new(key, AES.MODE_ECB)
plaintext = b'Hello World 123'
ciphertext = cipher.encrypt(plaintext)

# 解密
cipher = AES.new(key, AES.MODE_ECB)
decrypted_text = cipher.decrypt(ciphertext)

print(decrypted_text.decode())

2. Java：

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

public class AESExample {

    public static void main(String[] args) throws Exception {
        byte[] key = "0123456789abcdef".getBytes();  // 16字节的密钥
        int blockSize = Cipher.getInstance("AES").getBlockSize();  // 获取AES的块长度

        // 加密
        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
        SecretKeySpec secretKeySpec = new SecretKeySpec(key, "AES");
        cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec);
        byte[] plaintext = "Hello World 123".getBytes();
        byte[] ciphertext = cipher.doFinal(plaintext);

        // 解密
        cipher.init(Cipher.DECRYPT_MODE, secretKeySpec);
        byte[] decryptedText = cipher.doFinal(ciphertext);

        System.out.println(new String(decryptedText));
    }
}

3. C#：

using System;
using System.Security.Cryptography;

public class AESExample
{
    public static void Main()
    {
        byte[] key = new byte[] { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef };  // 16字节的密钥
        int blockSize = Aes.Create().BlockSize / 8;  // 获取AES的块长度

        // 加密
        using (Aes aes = Aes.Create())
        {
            aes.Mode = CipherMode.ECB;
            aes.Key = key;
            byte[] plaintext = System.Text.Encoding.UTF8.GetBytes("Hello World 123");
            byte[] ciphertext = aes.CreateEncryptor().TransformFinalBlock(plaintext, 0, plaintext.Length);

            // 解密
            aes.Mode = CipherMode.ECB;
            aes.Key = key;
            byte[] decryptedText = aes.CreateDecryptor().TransformFinalBlock(ciphertext, 0, ciphertext.Length);

            Console.WriteLine(System.Text.Encoding.UTF8.GetString(decryptedText));
        }
    }
}

以上是使用常用编程语言中的一些示例代码，用于展示如何设置AES密钥长度和块长度。请注意，在实际使用时，密钥长度和块长度应根据具体的安全需求进行选择和设置。