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To reverse a string, use the Array. Reverse() method.We have set a method and passed the string value as “Henry” −public static string ReverseFunc(string str) { char[] ch = str.ToCharArray(); Array.Reverse(ch); return new string(ch); }In the above method, we have converted the string into character array −char[] ch = str.ToCharArray();Then the Reverse() method is used −Array.Reverse(ch);
Format DateTime using String.Format method.Let us see an example −Exampleusing System; static class Demo { static void Main() { DateTime d = new DateTime(2018, 2, 8, 12, 7, 7, 123); Console.WriteLine(String.Format("{0:y yy yyy yyyy}", d)); Console.WriteLine(String.Format("{0:M MM MMM MMMM}", d)); Console.WriteLine(String.Format("{0:d dd ddd dddd}", d)); } }Above we have first set the DateTime class object −DateTime d = new DateTime(2018, 2, 8, 12, 7, 7, 123);To format, we have used the String.Format() method and displayed date in different formats.String.Format("{0:y yy yyy yyyy}", d) String.Format("{0:M MM MMM MMMM}", d) String.Format("{0:d dd ddd dddd}", d
Let’s say the following is the string −WelcomeAfter reversing the string, the words should be visible like −emocleWUse the reverse() method and try the following code to reverse words in a string −Exampleusing System; using System.Linq; class Demo { static void Main() { string str = "Welcome"; // reverse the string string res = string.Join(" ", str.Split(' ').Select(s => new String(s.Reverse().ToArray()))); Console.WriteLine(res); } }
To place spaces in between words starting with capital letters, try the following example −Firstly, set the string.var str = "WelcomeToMyWebsite";As you can see above, our string isn’t having spaces before capital letter. To add it, use LINQ as we have done below −str = string.Concat(str.Select(x => Char.IsUpper(x) ? " " + x : x.ToString())).TrimStart(' ');The following is the complete code to place spaces between words beginning with capital letters −Exampleusing System; using System.Linq; class Demo { static void Main() { var str = "WelcomeToMyWebsite"; Console.WriteLine("Original String: "+str); ... Read More
ArrayList is a non-generic type of collection in C# that dynamically resizes.Let us see how to initialize ArrayList in C# −ArrayList arr= new ArrayList();Add an item to an Array List −ArrayList arr1 = new ArrayList(); arr1.Add(30); arr1.Add(70);Let us see the complete example to implement ArrayList in C#. Here we have two array lists. The 2nd array list is appended to the first list.Exampleusing System; using System.Collections; public class MyClass { public static void Main() { ArrayList arr1 = new ArrayList(); arr1.Add(30); arr1.Add(70); ArrayList arr2 = ... Read More
To initialize a HashSet.var h = new HashSet(arr1);Above, we have set an array in the HashSet. The following is the array −string[] arr1 = { "electronics", "accessories”, "electronics", };The following is an example showing how to implement HashSet in C# −Exampleusing System; using System.Collections.Generic; using System.Linq; class Program { static void Main() { string[] arr1 = { "electronics", "accessories”, "electronics", }; Console.WriteLine(string.Join(",", arr1)); // HashSet var h = new HashSet(arr1); // eliminates duplicate words string[] arr2 = h.ToArray(); Console.WriteLine(string.Join(",", arr2)); } }
Java has a final keyword, but C# does not have its implementation. For the same implementation, use the sealed keyword.With sealed, you can prevent overriding of a method. When you use sealed modifiers in C# on a method, then the method loses its capabilities of overriding. The sealed method should be part of a derived class and the method must be an overridden method.The following example won’t allow you to override the method display() because it has a sealed modifier for the ClassTwo derived class.ClassOne is our base class, whereas ClassTwo and ClassThree are derived classes −Exampleclass ClassOne { ... Read More
Java has a final keyword, but C# does not have its implementation. Use the sealed or readonly keyword in C# for the same implementation.The readonly would allow the variables to be assigned a value only once. A field marked "read-only", can only be set once during the construction of an object. It cannot be changed.Exampleclass Employee { readonly int age; Employee(int age) { this.age = age; } void ChangeAge() { //age = 27; // Compile error } }Above, we have set the age field as readonly, which once assigned cannot be changed.
HashSet in C# eliminates duplicate strings or elements in an array.In C#, it is an optimized set collection.Let us see an example to remove duplicate strings using C# HashSet −Exampleusing System; using System.Collections.Generic; using System.Linq; class Program { static void Main() { string[] arr1 = { "one", "two", "two", "one", "three" }; Console.WriteLine(string.Join(",", arr1)); // HashSet var h = new HashSet(arr1); // eliminates duplicate words string[] arr2 = h.ToArray(); Console.WriteLine(string.Join(",", arr2)); } }To declare HashSet.var h = new HashSet
Declaring an array does not initialize the array in the memory. When the array variable is initialized, you can assign values to the array.Array is a reference type, so you need to use the new keyword to create an instance of the array. For example, assign the values like the following statement −double[] price = new double[5]; price[0] = 3245.50; price[1] = 1234.50; price[2] = 8765.50; price[3] = 5784.50; price[4] = 6576.50;We assigned five values above to the price array. You can assign values to the array at the time of declaration.double[] price = new double[5] {3245.50, 1234.50, 8765.50, 6576.50;};