C# Convert Char Array, String

Convert or change

A char array can be converted into a string. It can be hard to remember how to do this. We review how to use the reference type string constructor. With the string constructor, we have many options available.

Constructor

Example

String face

First, we see the approach you can use to convert the char array. This is interesting because you see the lowercase string type has a constructor.
Unlike int
or char,
a string is a reference type. Here we initialize a char array.

Char Array
Based on:

.NET 4.5

Program that converts char array: C#

using System;

class Program
{
    static void Main()
    {
	// Part A: 15 character array.
	char[] c = new char[15];
	c[0] = 'O';
	c[1] = 'n';
	c[2] = 'l';
	c[3] = 'y';
	c[4] = ' ';
	c[5] = 'T';
	c[6] = 'h';
	c[7] = 'e';
	c[8] = ' ';
	c[9] = 'L';
	c[10] = 'o';
	c[11] = 'n';
	c[12] = 'e';
	c[13] = 'l';
	c[14] = 'y';

	// Part B: 15 character string.
	string s = new string(c);
	Console.WriteLine(s);
    }
}

Output

Only The Lonely
New keyword, constructor invocation

The first part shows the 15 characters in the char array assigned to letters. Recall that char is two bytes. Next, we use the new string() constructor. It is the same as a regular constructor such as new Form(), but is lowercase.

CharString type

String keyword. The lowercase "string" type is actually an alias for the String reference type. Strings are reference types. This means they reference external data—this is allocated on the managed heap.

Discussion

File: text page

The new string constructor is overall very efficient when compared to other approaches. It is the fastest way to make a new string in many cases. I use it in my performance-sensitive web program.

String Constructor

Tip:It is much faster than manually appending characters to your string, or using StringBuilder.

StringBuilder

MSDN indicates that the String Constructor(Char[]) "Initializes a new instance of the String class to the value indicated by an array of Unicode characters." If you pass the constructor null, you get an empty string (not a null one).

String Constructor: MSDN

Summary

We used the overloaded string constructor shown to instantiate a new string object from an array. You can run the example console app to prove the method works and will work in your program.


C#: Cast