C# encrypt PHP decrypt using RSA

Question

I'm trying to build a simple RSA encryption decrpytion process between C# and PHP. I've accomplished encrypting in PHP and decrpyt in C# with phpseclib(http://phpseclib.sourceforge.net/). However I'm getting "Decryption error in C:\xampp\htdocs\Crypt\RSA.php on line 2103" which is this part:

if ($lHash != $lHash2) {
        user_error('Decryption error', E_USER_NOTICE);
        return false;
    }

the encryption in C# I used this bunch of code:

RSACryptoServiceProvider rsaCryptoServiceProvider = new RSACryptoServiceProvider(dwKeySize);
        rsaCryptoServiceProvider.FromXmlString(publickey);
        int keySize = dwKeySize / 8;
        byte[] bytes = Encoding.UTF32.GetBytes(inputString);
        // The hash function in use by the .NET RSACryptoServiceProvider here is SHA1
        // int maxLength = ( keySize ) - 2 - ( 2 * SHA1.Create().ComputeHash( rawBytes ).Length );
        int maxLength = keySize - 42;
        int dataLength = bytes.Length;
        int iterations = dataLength / maxLength;
        StringBuilder stringBuilder = new StringBuilder();
        for (int i = 0; i <= iterations; i++)
        {
            byte[] tempBytes = new byte[(dataLength - maxLength * i > maxLength) ? maxLength : dataLength - maxLength * i];
            Buffer.BlockCopy(bytes, maxLength * i, tempBytes, 0, tempBytes.Length);
            byte[] encryptedBytes = rsaCryptoServiceProvider.Encrypt(tempBytes, true);
            // Be aware the RSACryptoServiceProvider reverses the order of encrypted bytes after encryption and before decryption.
            // If you do not require compatibility with Microsoft Cryptographic API (CAPI) and/or other vendors.
            // Comment out the next line and the corresponding one in the DecryptString function.
            Array.Reverse(encryptedBytes);
            // Why convert to base 64?
            // Because it is the largest power-of-two base printable using only ASCII characters
            stringBuilder.Append(Convert.ToBase64String(encryptedBytes));
        }
        string ciphertext = stringBuilder.ToString();

and my basic PHP code to decrpyt:

$rsa->loadKeyfromXML($privatekey);  
$ciphertext = file_get_contents('cipher.txt');
$ciphertext = base64_decode(strrev($ciphertext));

//$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_PKCS1);

$plaintext = $rsa->decrypt($ciphertext);

I've tried PKC1 it also gave another error in Crypt/RSA.php

Answer 1

yay I just found solution myself. I changed the line in encryption:

byte[] bytes = Encoding.UTF32.GetBytes(inputString);  ==> byte[] bytes = Encoding.Default.GetBytes(inputString);

and also as @Ryan said:

$ciphertext = base64_decode(strrev($ciphertext));  ==> $ciphertext = strrev(base64_decode($ciphertext));

Thanks for your attemps.