C# extension

Sunday, October 28, 2012

Validation is a boxing value is default

public static bool IsDefault(this object o)
{
    if (o == null)
    {
        return true;
    }
    return (o.GetType().IsValueType)  
        ?  Activator.CreateInstance(o.GetType()).Equals(o)
        : false;
}

Friday, August 5, 2011

Extension of paging in LINQ

Implementation:

public static IEnumerable<T> Paging<T>(this  IQueryable<T> query,int rowCount, int pageIndex)
{
    return  query        
        .Skip((pageIndex - 1) * rowCount)
        .Take(rowCount);
}

Using:

private void TestMethod()
{
    Random rnd = new Random();
    List<Foo> fooList = new List<Foo>();
    for (int i = 0; i < 20; i++)
    {
        fooList.Add(
                new Foo
                {
                    ID = rnd.Next(100),
                    Name = Membership.GeneratePassword(5, 0)
                }
            );
    }
 
    var query = fooList.OrderBy(item => item.ID).AsQueryable();
 
   Console.WriteLine("Attempt 1");
    query.Paging(10, 1)
       .ToList()
       .ForEach(
        item => Console.WriteLine(item.ID + ": " + item.Name)
        );
    Console.WriteLine("Attempt 2");
    query.Paging(5, 2)
        .ToList()
        .ForEach(
        item => Console.WriteLine(item.ID + ": " + item.Name)
        );
}

Class:

public class Foo
{
    public int ID { get; set; }
    public string Name { get; set; }
}

Tuesday, July 19, 2011

Convert UTF-8 to Unicode extension

The code:

public static string UTF8ToUnicode(this string input)
{
    return Encoding.Unicode.GetString(
                        Encoding.Convert(Encoding.UTF8,
                                            Encoding.Unicode,   
                                            Encoding.UTF8.GetBytes(
                                                        input)));
}

Example:

 
string txt ="Hello, World!";
txt.UTF8ToUnicode();

Monday, July 18, 2011

Encrypt and Decrypt extention

Today we offer Encrypt/Decrypt extension by MD5 algorithm:

/// <summary>

/// Encrypt input by MD5

/// </summary>

/// <param name="input"></param>

/// <returns></returns>

public static string Encrypt(this string input)

{

    using (MD5 md5Hash = MD5.Create())

    {

        // Convert the input string to a byte array and compute the hash.

        byte[] data = md5Hash.ComputeHash(Encoding.UTF8.GetBytes(input));

        // Create a new Stringbuilder to collect the bytes

        // and create a string.

        StringBuilder stringBuilder = new StringBuilder();

        // Loop through each byte of the hashed data 

        // and format each one as a hexadecimal string.

        Array.ForEach(data,

             item => stringBuilder.Append(item.ToString("x2"))

            );

        // Return the hexadecimal string.

        return stringBuilder.ToString();

    }

}

/// <summary>

/// Verify a hash against a string.

/// </summary>

/// <param name="input"></param>

/// <param name="hash"></param>

/// <returns></returns>

public static bool Decrypt(this string hash, string input )

{

    // Hash the input.

    string hashOfInput = Encrypt(input);

    // Create a StringComparer an compare the hashes.

    StringComparer comparer = StringComparer.OrdinalIgnoreCase;

    return (comparer.Compare(hashOfInput, hash) == default(int)) ? true : false;

}

Example:

public class Foo

{

    public string UserName { get; set; }

    public string Password { get; set; }

} 

//Your code

Foo foo = new Foo

{

    UserName = "admin",

    //Encrypt

    Password = "12345".Encrypt()

};

//Decrypt

bool isValid = foo.Password.Decrypt("12345");

From Framework 1.1 I’m use in static class for serialize and deserialize objects. In Framework 2.0 C# got generics and class make away with word “object” but evolution is go on and time has come to create Serializer as extension:

using System;

using System.IO;

using System.Runtime.Serialization;

using System.Runtime.Serialization.Formatters.Binary;

using System.Runtime.Serialization.Formatters.Soap;

using System.Text;

using System.Xml.Serialization;

static class Serializer

{

/// <summary>

/// Deserializes from binary.

/// </summary>

/// <param name="type">Type.</param>

/// <param name="bytes">buffer</param>

/// <returns></returns>

public static T DeserializeFromBinary<T>(this byte[] bytes) where T : class

{

    T obj = default(T);

    MemoryStream memoryStream = new MemoryStream(bytes);

    try

    {

        BinaryFormatter binaryFormatter = new BinaryFormatter();

        obj = (T)binaryFormatter.Deserialize(memoryStream);

    }

    catch (SerializationException exception)

    {

        throw;

    }

    return obj;

}

/// <summary>

/// Deserializes from file.

/// </summary>

/// <param name="type">Type.</param>

/// <param name="path">Path.</param>

/// <returns></returns>

public static T DeserializeFromFile<T>(this string path) where T : class

{

    T obj = default(T);

    FileStream fileStream = new FileStream(path, FileMode.Open);

    try

    {

        BinaryFormatter binaryFormatter = new BinaryFormatter();

        obj = (T)binaryFormatter.Deserialize(fileStream);

    }

    catch (SerializationException exception)

    {

        throw;

    }

    finally

    {

        fileStream.Close();

    }

    return obj;

}

/// <summary>

/// Deserializes from string that contains SOAP.

/// </summary>

/// <param name="type">Type.</param>

/// <param name="soap">S.</param>

/// <returns></returns>

public static T DeserializeFromSoap<T>(this string soap) where T : class

{

    T obj = default(T);

    MemoryStream memoryStream = new MemoryStream(new UTF8Encoding().GetBytes(soap));

    try

    {

        SoapFormatter soapFormatter = new SoapFormatter();

        obj = (T)soapFormatter.Deserialize(memoryStream);

    }

    catch (SerializationException exception)

    {

        throw;

    }

    return obj;

}

/// <summary>

/// Deserializes from XML string

/// </summary>

/// <param name="type">Type.</param>

/// <param name="s">S.</param>

/// <returns></returns>

public static T DeserializeFromXml<T>(this string xml) where T : class

{

    T obj = default(T);

    try

    {

        XmlSerializer xmlSerializer = new XmlSerializer(typeof(T));

        obj = (T)xmlSerializer.Deserialize(new StringReader(xml));

    }

    catch (SerializationException exception)

    {

        throw;

    }

    return obj;

}

/// <summary>

/// Deserializes from XML file.

/// </summary>

/// <param name="type">Type.</param>

/// <param name="xmlFilePath">file path.</param>

/// <returns></returns>

public static T DeserializeFromXmlFile<T>(this string xmlFilePath) where T : class

{

    T obj = default(T);

    FileStream fileStream = default(FileStream);

    try

    {

        fileStream = new FileStream(xmlFilePath, FileMode.Open);

        XmlSerializer xmlSerializer = new XmlSerializer(typeof(T));

        obj = (T)xmlSerializer.Deserialize(fileStream);

    }

    catch (Exception exception)

    {

        throw;

    }

    finally

    {

        fileStream.Close();

    }

    return obj;

}

/// <summary>

/// Gets the size of the object.

/// </summary>

/// <param name="obj">O.</param>

/// <returns></returns>

public static long GetByteSize<T>(this T obj) where T : class

{

    BinaryFormatter binaryFormatter = new BinaryFormatter();

    MemoryStream memoryStream = new MemoryStream();

    binaryFormatter.Serialize(memoryStream, obj);

    return memoryStream.Length;

}

/// <summary>

/// Serializes to binary stream.

/// </summary>

/// <param name="obj">Obj.</param>

/// <returns></returns>

public static byte[] SerializeToBinary<T>(this T obj) where T : class

{

    byte[] buffer = new byte[0x9c4];

    MemoryStream memoryStream = new MemoryStream();

    try

    {

        BinaryFormatter binaryFormatter = new BinaryFormatter();

        binaryFormatter.Serialize(memoryStream, obj);

        memoryStream.Seek(0, SeekOrigin.Begin);

        if (memoryStream.Length > buffer.Length)

        {

            buffer = new byte[memoryStream.Length];

        }

        buffer = memoryStream.ToArray();

    }

    catch (Exception exception)

    {

        throw;

    }

    finally

    {

        memoryStream.Close();

    }

    return buffer;

}

public static void SerializeToBinary<T>(this T obj, string filePath) where T : class

{

    SerializeToBinary(obj, filePath, FileMode.Create);

}

public static void SerializeToBinary<T>(this T obj, string filePath, FileMode mode) where T : class

{

    FileStream fileStream = default(FileStream);

    BinaryFormatter binaryFormatter = new BinaryFormatter();

    try

    {

        fileStream = new FileStream(filePath, mode);

        binaryFormatter.Serialize(fileStream, obj);

    }

    catch (Exception exception)

    {

        throw;

    }

    finally

    {

        fileStream.Close();

    }

}

public static string SerializeToSoap<T>(this T obj) where T : class

{

    string returnValue = string.Empty;

    MemoryStream memoryStream = new MemoryStream();

    try

    {

        SoapFormatter soapFormatter = new SoapFormatter();

        soapFormatter.Serialize(memoryStream, obj);

        memoryStream.Seek(0, SeekOrigin.Begin);

        returnValue = Encoding.ASCII.GetString(memoryStream.ToArray());

    }

    catch (Exception exception)

    {

        throw;

    }

    finally

    {

        memoryStream.Close();

    }

    return returnValue;

}

public static void SerializeToSoap<T>(this T obj, string filePath, FileMode mode) where T : class

{

    FileStream fileStream = default(FileStream);

    SoapFormatter soapFormatter = new SoapFormatter();

    try

    {

        fileStream = new FileStream(filePath, mode);

        soapFormatter.Serialize(fileStream, obj);

    }

    catch (SerializationException exception)

    {

        throw;

    }

    finally

    {

        fileStream.Close();

    }

}

public static string SerializeToXml<T>(this T obj) where T : class

{

    string returnValue = string.Empty;

    MemoryStream memoryStream = new MemoryStream();

    try

    {

        XmlSerializer serializer = new XmlSerializer(typeof(T));

        serializer.Serialize(memoryStream, obj);

        memoryStream.Seek(0, SeekOrigin.Begin);

        returnValue = Encoding.ASCII.GetString(memoryStream.ToArray());

    }

    catch (SerializationException exception)

    {

        throw;

    }

    finally

    {

        memoryStream.Close();

    }

    return returnValue;

}

public static void SerializeToXmlFile<T>(this T obj, string filePath, FileMode mode) where T : class

{

    FileStream fileStream = default(FileStream);

    XmlSerializer serializer = new XmlSerializer(typeof(T));

    try

    {

        fileStream = new FileStream(filePath, mode);

        serializer.Serialize(fileStream, obj);

    }

    catch (Exception exception)

    {

        throw;

    }

    finally

    {

        fileStream.Close();

    }

}

}

A method limited to using by class only but not prevent from errors. Examples:

public class Foo

{

    public int ID { get; set; }

    public string Name { get; set; }

}

//……………………

//Your code

Foo foo = new Foo

{

    ID = 5,

    Name = "John Smith"

};

//Serialize

string xml = foo.SerializeToXml();

//Deserialize

Foo newFoo = xml.DeserializeFromXml<Foo>();

//Serialize

foo.SerializeToXmlFile(@"C:\file.xml", System.IO.FileMode.CreateNew);

//Deserialize

byte[] bytes = //...;

bytes.DeserializeFromBinary<Foo>();

// And more extension is working by same  calling

Enjoy!

IsDefault extension

Known reserved word of C# default(TYPE) can be used as very usability feature as IsDefault():

public static bool IsDefault<T>(this T value)

{

    return value == null || value.Equals(default(T));

}

A can be available in every place in the project by next using:

int number = 5;

if (number.IsDefault())

{ 

    //...

}

It's short and simple alternative to usual:

if (number == default(int))  

The extension work nice with objects:

class Foo

{

    public int Id { get; set; }

    public int Name { get; set; }

}

//...

Foo foo = new Foo();

if (!foo.IsDefault())

{

    //....

    foo.Name = "John Smith";

}

Enjoy!

Sunday, July 17, 2011

ForEach for ICollection<T>

I like inline function list.ForEach() for IList but always disappointed regarding to ICollection. In order to run loop requered to create Enumerator and etc. Therefore I offering short solutions:

public static void ForEach<T>(this IEnumerable<T> collection,Action<T> action)

{

    IEnumerator<T> enumerator = collection.GetEnumerator();

    while (enumerator.MoveNext())

    {

        action.Invoke(enumerator.Current);

    }

}

A using:

Dictionary<string, int> dic = new Dictionary<string, int>();

dic.Add("a", 123);

dic.Add("b",456);

//Example 1

dic.ForEach(item => Console.WriteLine(item.Key));

Action<string, int> print = (key, value) =>

{

    Console.WriteLine(

        string.Format("Key: {0}, value: {1}", key, value)

    );

};

//Example 2

dic.ForEach(item => print(item.Key, item.Value));

Enjoy.