Introduction
In this article, you will learn how to initialize a string array with default values using the new keyword and a specified size for the Array. An array is a collection of elements of the same type that can be accessed using an index. In the case of a string array, each element is a string value. When you create a new array in C#, it is initially filled with default values. For a string array, the default value is null. However, in some cases, you may want to initialize a string array with a specific default value instead of null. This can be useful, for example, when creating a new array to hold user input or when you want to ensure that all elements of the Array have a specific value to start with.
Several ways to initialize a string array with default values in C# include using the new keyword or the Enumerable.Repeat method. Initializing a string array with default values using the new keyword
The most basic way to initialize a string array with default values is to use the new keyword and specify the size of the Array. This will create a new string array with all elements set to null by default.
string[] myArray = new string[5];
This creates a string array with five elements; each initialized to null. You can access individual elements of the Array using an index like this.
string firstElement = myArray[0];
Initializing a string array with a specific default value using the Enumerable.Repeat method If you want to initialize a string array with a particular default value instead of null, you can use the Enumerable.repeat method to create a sequence of values and then convert it to an array using the Array () method.
Method 1. Enumerable.Repeat in C#
This method uses the Enumerable.Repeat the() method to the sequence of a repeated value and then convert the sequence back to the Array using the ToArray() method. This is Defer's execution in the implementation. The instant return value is an object with all the data needed to complete the action. The GetEnumerator method of the object, or for each in C#, can be used to enumerate the object before running the query represented by this method in C#.
The following code example shows the usage of this method.
public class Program
{
public static void Main()
{
int element = 2;
int count = 20;
int[] array = Enumerable.Repeat(element, count).ToArray();
Console.WriteLine(String.Join(",", array));
}
}
This C# program initializes an integer variable element to 2, and an integer variable count to 20. It then creates an integer array with a length of count. Next, it uses a for loop to iterate through each element of the Array, setting each element to the value of the element (which is 2 in this case).
Finally, it prints out the contents of the Array using the String.Join method to concatenate the elements of the Array into a comma-separated string.
Output
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Method 2. Loop in C#
A for-loop is the recommended method for initializing an array. The code below shows how to use a for-loop to fill an array with an initial value in C#. It's common to want to run a particular block of statements a given number of times. Typing those statements the required number of times is one potential solution. However, the number of repetitions might not be known beforehand (during build time) or insufficient (say 100000) in C#.
The loop is the ideal solution to this issue. Programmers use loops to run a particular block of statements until a certain condition is.
public class Program
{
public static void Main()
{
int element = 2;
int count = 20;
int[] array = new int[count];
for (int i = 0; i < count; i++)
{
array[i] = element;
}
Console.WriteLine(String.Join(",", array));
}
}
This is a C# program that creates an array of integers, initializes each element to the value of 2, and then prints out the Array using the Console.WriteLine method. Here's a brief explanation of what each line of the code does
1. The line public class Program declares a public class named "Program."
2. The line public static void Main() declares a public static method named "Main," which is the program's entry point.
3. The line int element = 2; declares an integer variable named "element" and initializes it to the value of 2.
4. The line int count = 20; declares an integer variable named "count" and initializes it to the value of 20.
5. The line int[] array = new int[count]; creates a new integer array named "array" with a length of "count" (which is 20 in this case).
6. The for loop starting on line 7 iterates through each element of the Array and sets it equal to the value of "element" (which is 2).
7. The line Console.WriteLine(String.Join(",," Array)); prints out the contents of the "array" variable, separating each element with a comma the String. The join method is used to concatenate the elements of the Array into a single string.
Output
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Method 3. Fill in C#
We can use the AArrayFill()method as of.NET Core 7.0 and.NET Standard 7.5 to get the following result.
Syntax
Array.Fill(array, value);
The first parameter represents the Array we want to fill, and the second parameter defines the value we want to give each array index. As this method is static and general, we can use it with arrays of any object type and are not required to instantiate the program class to utilize it.
In addition to these two parameters, it is important to note that the Fill function offers an overload where we can give an integer start index and a variable called count. Therefore, the outcome will be slightly different if we run this method while passing these two extra parameters.
Array.Fill(array, value, 2, 20);
Once you send two as the start index and 20 as the count, our Array will keep all the previous values except for indexes 2 and 20.
These indexes are going to receive the new value that is represented as our second parameter.
The Array is the most straightforward approach.Fill() is a method that uses a for-loop to fill an array with a single value in C#.
public class Program
{
public static void Main()
{
int element = 2;
int count = 20;
int[] array = new int[count];
Array.Fill(array, element);
Console.WriteLine(String.Join(",", array));
}
}
This C# program creates an array of integers with a specified length of 20 and fills it with a value of 2 using the Array.Fill() method. It then prints the Array to the Console using the String.Join() method, which concatenates the elements of the Array into a string separated by commas.
Output
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Conclusion
In this article, you will learn about the code that taught us How to initialize a string array with default values in C#. Also, check out Working with Arrays in C# (code included), and check out Working with Arrays in C# (code included)
Also, check out Properties In C# to learn more about properties in C#.
FAQs
Q. How do you find the length of a string in C#?
A. To find the length of a string in C#, you can use the Length property of the String. Here's an example
string myString = "Hello, world!";
int stringLength = myString.Length;
In this example, the stringLength variable is assigned the value 13, which is the length of the myString String.
Q. How do you convert a string to an integer in C#?
A. You can use the int to convert a string to an integer in C#.Parse() method.
Here's an example
string myString = "123";
int myInt = int.Parse(myString);
In this example, the myInt variable is assigned the value 123, which is the integer representation of the myString String.
Q. How do you loop through an array in C#?
A. To loop through an array in C#, you can use a for loop with the Array's Length property. Here's an example
int[] myArray = { 1, 2, 3, 4, 5 };
for (int i = 0; i < myArray.Length; i++)
{
Console.WriteLine(myArray[i]);
}
In this example, the for loop iterates through each element in the myArray Array and prints its value to the Console.
Q. How do you check if a string contains a substring in C#?
A. To check if a string contains a substring in C#, you can use the Contains() method of the String. Here's an example
string myString = "Hello, world!";
bool containsSubstring = myString.Contains("world");
In this example, the containsSubstring variable is assigned the value true since the myString String contains the substring "world."