Tutorial and something more …

Hello, before I start to write just to remind you that we need a writer.So if you want to write on our blog please contact us at contact@zeusoft.net.

Ok, in this tutorial i will teach you how you can optimize your C# code.When you have a few “millions ” lines of code, your program may run slow.So you need to optimize your code using these tips:Loops

1. For loops is twice faster then foreach loops.That foreach loop:

static private void ForeachLoop(ArrayList SomeList)
{
        int id = 0;

        foreach (int i in List)
        {
                // Do something with the object ...
                id = i;
        }
}

is twice faster like that:

static private void ForLoop(ArrayList SomeList)
{
        int id = 0;
        int count = SomeList.Count;

        for (int i = 0; i < SomeList.Count; i++)
        {
                // Do something with the object ...
                id = (int)SomeList[i];
        }
}

2. Boxing and unboxing

static private void BoxingAndUnboxing()
{
        int i = 222;
        object o = i; // Implicit boxing

        i = 456; // Change the contents of i

        int j = (int)o; // Unboxing (if types are incompatible this may trow an exception)
}

You dont have to use boxing and unboxing, and it’s faster:

static private void NoBoxingAndUnboxing()
{
        int i = 123;

        i = 456; // Change the contents of i

        int j = i; // Compatible types
}

3.Exceptions

Trowing and catching an exception is 1000 slower than checking for an error code:

static void FunctionThatThrows()
{
        throw new Exception();
}

1000 times faster

static int FunctionThatReturnsErrorCode()
{
        return -1;
}

4.Collections
Using actual size for data rather than some default size increases performance up to 50%

ht = new Hashtable(count); // Creates an Hashtable using size = Count
LoadData(ht, count);

// Display results
Display.Show(1, "Elapsed time: " + t.ElapsedTime.ToString() + " ms \n", 0);

// End of the demo
Display.Show(-1, "Collections demo end.\n", 1);

static private void LoadData(Hashtable ht, int Count)
{
        // Fill the employee collection with data
        for (int i = 0; i < Count; i++)
        {
                Employee employee = new Employee(i, "Employee" + i.ToString());
                ht.Add(i, employee);
        }
}

5.Garbage collection
80% slower than doing nothing:

static private void Test(int count)
{
        DisposableObject []obj = new DisposableObject[count];
        for(int i=0;i

best solution:

static private voide LetDotnetCleanup(int count)
{

        // Start performance timing
        t.Start();
        int count=int.Parse(args[0]);
        DisposableObject []obj = new DisposableObject[count];
        for(int i=0;i

6.Stack and Heap
N structures are Log(N) faster to allocate than N classes:

        class ClassObject
        {
                public int x;
        }

        struct StructObject
        {
                public int x;
        }
        //alloc structs
        tAllocation.Start();
        for (i = 0; i < repeat; i++) // repeat to get more acurate timing
                s = new StructObject();
        tAllocation.Stop();

        //alloc objects
        for (i = 0; i < repeat; i++) // repeat to get more acurate timing
                c = new ClassObject();

Reference: http://csharpcomputing.com/Tutorials/Lesson23.htm