How to count a string within another string in VB.NET/C#

How to get number of given string using C#/VB.NET

After a lull I wanted to start somewhere; here is what I got for now (thanks to Arivuchutarji who initiated this debate).

We have come across many situations where we need to count a string within other.

There are three ways to do (infact two)

1. Linq
2. A Do While loop using IndexOf
3. Regular Expressions

Here is the LINQ one - it applies to characters and not strings (appreciate if someone could post searching a text within a string)

        Dim sCollection As String
        sCollection = "this is a string with some text repeated and some not"
        Dim count As Integer
        count = (From sText In sCollection
                         Where sText = "s"
                         Select sText).Count

The second one appears primitive - but a foolproof method

        Dim cntStr = -1, i1, iStart As Integer
        Dim searchString As String
        searchString = "some"
        Do While i1 <> -1
            i1 = sCollection.IndexOf(searchString, iStart)
            iStart = i1 + 1
        Loop

And finally, my favorite regular expressions - code is clean if you use this

        cntStr = RegularExpressions.Regex.Matches(sCollection, "some").Count

Appreciate your comments on this

How to Change Permission of Folder in Visual Basic / C#

VB.NET Set Folder Permission / C# Set Folder Permission


In this snippet we create a new directory and set the permission of it to Fullcontrol using ACL.

private static void ChangePermissionOfDir()
        {
            //Folder
            DirectoryInfo NewDir = Directory.CreateDirectory(@"C:\Temp\Te21");

            DirectorySecurity dSecur = NewDir.GetAccessControl();

            FileSystemAccessRule fAccess = new FileSystemAccessRule("Everyone",FileSystemRights.FullControl,AccessControlType.Allow  );


            dSecur.AddAccessRule(fAccess);

            NewDir.SetAccessControl(dSecur);
 
    
        }

How to Convert a String to Array of Characters

The following snippet converts a string to a Character Array using CharArray

private static void String2CharArray()        {
            string s1 = "This is a string";
            Char[] ArrayofChars;
            ArrayofChars = s1.ToCharArray();
            Console.WriteLine(s1);
            foreach (char c1 in ArrayofChars)
                Console.WriteLine(c1);
        }

Queue in C# / Add and Remove items from Queue in C# (.NET)

Queues are common in real world - Flight checkins to School. Here is the way you can use it in C#

private static void CustomerServiceQueue()
        {
            Queue CSQ = new Queue();

            CSQ.Enqueue("Gautam");
            CSQ.Enqueue("Nargis");
            CSQ.Enqueue("Beth");
            CSQ.Enqueue("Slobodan");

            Console.WriteLine("Peeking Queue: {0}", CSQ.Peek());

            Console.WriteLine("Check if CSQ Contains Beth : {0}", CSQ.Contains("Beth"));

            while (CSQ.Count > 0)
            {
                Console.WriteLine(CSQ.Dequeue());
            }
           

        }

Contains checks for presence of the given object in the queue. Peek returns the first element from the queue

Dequeuue does the same as Peek, however, it also removes the object

How to Override ToString Method in C# (VB.NET)

Customize ToString Method in C# (VB.NET)

Overriding ToString Method has its own advantages.

For example, the following class has four fields

public class ClassExec
    {
        string _Name;
        
        public string Name
        {
            get { return _Name; }
            set { _Name = value ;}
        }

        public string Source
        {
            get;
            set;
        }

        public string Destination
        { get; set; }

        public DateTime  DOT
        {
            get;
            set;
        }

If you try to use the ClassExec.ToString() method it will return the fully qualified Class name as default. This doesn't help us much.

Instead let us override the ToString method to return the four fields in a formatted way

public override string ToString()
        {
            return (Name + ' ' + Source + ' ' + Destination + ' ' + DOT);
        }

The following code will now produce the desired output:

ClassExec cls = new ClassExec();
            cls.Name = "Jackob Johnson";
            cls.Source = "Socchi";
            cls.Destination = "Moscow";
            cls.DOT = DateTime.Parse("12-Jan-2012");

            Console.WriteLine(cls.ToString());

System.Xml.Serialization.XmlSerializer.XmlSerializer() is inaccessible due to its protection level

One reason for this error is if you haven't mentioned the type when you initialize the XmlSerializer object

XmlSerializer Xser = new XmlSerializer()

can be replaced with

XmlSerializer Xser = new XmlSerializer(this.GetType() );

How to CreateFolder in C# (.NET) / How to Create a Directory in C# (VB.NET)

How to check if a directory exists in C# / How to check if a folder exists in C#

Many times backups are created in a new folder with name as date etc. The following snippet checks if directory exists in the particular path and creates it

private static void CreateFolder()
        {
        //This example creates a new folder under MyDocuments

            string folderName = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);

            string userName = Environment.UserName;

            folderName = Path.Combine(folderName, userName);

            if (Directory.Exists(folderName) == false)
            {
                Directory.CreateDirectory(folderName);
            }


        }

How to combine two paths in .NET

The example combines two paths using Path.Combine method.

See also:

• How to Download File from Website using C# (.NET)
• Check if file exists using C# (.NET)
• Copying Files using .Net Functions