public class StringHelpers
{
public const char QUERY_STRING_DELIMITER =
'&';
private static RijndaelManaged _cryptoProvider;
//128 bit encyption: DO NOT CHANGE
private static readonly byte[] Key = {
18,
19,
8,
24,
8,
22,
2,
25,
17,
5,
11,
9,
13,
15,
06,
9 };
private static readonly byte[] IV = {
14,
2,
16,
7,
5,
9,
33,
23,
23,
47,
16,
12,
1,
32,
25,
9 };
static StringHelpers()
{
_cryptoProvider =
new RijndaelManaged();
_cryptoProvider.Mode =
CipherMode.CBC;
_cryptoProvider.Padding =
PaddingMode.PKCS7;
}
public static string Encrypt(
string unencryptedString)
{
return Encrypt(unencryptedString,
string.Empty);
}
public static string Encrypt(
string unencryptedString,
string myKey)
{
//byte[] bytIn = ASCIIEncoding.ASCII.GetBytes(unencryptedString);
//如果內容有unicode的話，要用utf8編碼
byte[] bytIn =
UTF8Encoding.UTF8.GetBytes(unencryptedString);
byte[] bytKey;
if(
string.IsNullOrEmpty(myKey)){
bytKey =
Key;
}else{
bytKey =
ASCIIEncoding.ASCII.GetBytes(myKey);
Array.Resize(ref bytKey,
16);
}
// Create a MemoryStream
MemoryStream ms =
new MemoryStream();
// Create Crypto Stream that encrypts a stream
CryptoStream cs =
new CryptoStream(ms, _cryptoProvider.CreateEncryptor(bytKey, IV), CryptoStreamMode.Write);
// Write content into MemoryStream
cs.Write(bytIn,
0, bytIn.Length);
cs.FlushFinalBlock();
byte[] bytOut =
ms.ToArray();
//因為url不能吃+所以要轉成@@@
return Convert.ToBase64String(bytOut).Replace(
"+",
"@@@");
}
public static string Decrypt(
string encryptedString)
{
return Decrypt(encryptedString,
string.Empty);
}
public static string Decrypt(
string encryptedString,
string myKey)
{
if (encryptedString.Trim().Length !=
0)
{
//如果有人改加密字串的話，解就會發生錯誤，所以錯誤就回傳空字串
try
{
// Convert from Base64 to binary 在解開前要先將@@@轉成+
byte[] bytIn = Convert.FromBase64String(encryptedString.Replace(
"@@@",
"+"));
byte[] bytKey;
if(
string.IsNullOrEmpty(myKey)){
bytKey =
Key;
}else{
bytKey =
ASCIIEncoding.ASCII.GetBytes(myKey);
Array.Resize(ref bytKey,
16);
}
// Create a MemoryStream
MemoryStream ms =
new MemoryStream(bytIn,
0, bytIn.Length);
// Create a CryptoStream that decrypts the data
CryptoStream cs =
new CryptoStream(ms, _cryptoProvider.CreateDecryptor(bytKey, IV), CryptoStreamMode.Read);
// Read the Crypto Stream
StreamReader sr =
new StreamReader(cs);
return sr.ReadToEnd();
}
catch
{
return "";
}
}
else
{
return "";
}
}
public static NameValueCollection DecryptQueryString(
string queryString)
{
return DecryptQueryString(queryString,
string.Empty);
}
public static NameValueCollection DecryptQueryString(
string queryString,
string myKey)
{
if (queryString.Length !=
0)
{
//Decode the string
string decodedQueryString =
HttpUtility.UrlDecode(queryString);
//Decrypt the string
string decryptedQueryString =
StringHelpers.Decrypt(decodedQueryString, myKey );
//Now split the string based on each parameter
string[] actionQueryString = decryptedQueryString.Split(
new char[] { QUERY_STRING_DELIMITER });
NameValueCollection newQueryString =
new NameValueCollection();
//loop around for each name value pair.
for (
int index =
0; index < actionQueryString.Length; index++
)
{
string[] queryStringItem = actionQueryString[index].Split(
new char[] {
'=' });
if(queryStringItem.Length >
1)
newQueryString.Add(queryStringItem[0], queryStringItem[
1]);
}
return newQueryString;
}
else
{
//No query string was passed in.
return null;
}
}
public static string EncryptQueryString(NameValueCollection queryString)
{
return EncryptQueryString(queryString,
string.Empty);
}
public static string EncryptQueryString(NameValueCollection queryString,
string myKey)
{
//create a string for each value in the query string passed in.
string tempQueryString =
"";
for (
int index =
0; index < queryString.Count; index++
)
{
tempQueryString += queryString.GetKey(index) +
"=" +
queryString[index];
if (index != queryString.Count -
1)
{
tempQueryString +=
QUERY_STRING_DELIMITER;
}
}
return EncryptQueryString(tempQueryString, myKey);
}
public static string EncryptQueryString(
string queryString)
{
return EncryptQueryString(queryString,
string.Empty);
}
public static string EncryptQueryString(
string queryString,
string myKey)
{
return "?" +
HttpUtility.UrlEncode(StringHelpers.Encrypt(queryString, myKey));
}
}
转载于:https://www.cnblogs.com/siyunianhua/p/3861455.html
