Tutorials

C# String GetHashCode() Method

Posted in C# Tutorial

Updated on Jan 11, 2024

By Mari Selvan

👁️ 83 - Views

⏳ 4 mins

💬 1 Comment

Photo Credit to CodeToFun

🙋 Introduction

In C# programming, strings are a fundamental data type, and various methods are available to work with them.

The GetHashCode() method is one such method provided by the System.String class.

It returns the hash code for the current string, which can be useful in scenarios like hashing for data storage or efficient search operations.

In this tutorial, we'll explore the usage and functionality of the GetHashCode() method in C#.

💡 Syntax

The syntax for the GetHashCode() method is as follows:

Syntax

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public override int GetHashCode();

The method is a member of the System.String class and is marked as override because it overrides the GetHashCode() method defined in the System.Object class.

📄 Example

Let's dive into an example to illustrate how the GetHashCode() method works.

Program.cs

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using System;

class Program {
  static void Main() {
    string sampleString = "Hello, C#!";

    // Get the hash code of the string
    int hashCode = sampleString.GetHashCode();

    // Output the hash code
    Console.WriteLine($"Hash code of the string: {hashCode}");
  }
}

💻 Testing the Program

Output

Hash code of the string: -1034815400

🧠 How the Program Works

In this example, the GetHashCode() method is used to obtain the hash code for the string "Hello, C#!" and then prints the result.

↩️ Return Value

The GetHashCode() method returns a 32-bit signed integer hash code that represents the value of the current string.

📚 Common Use Cases

The GetHashCode() method is commonly used in scenarios where hashing is required, such as when storing strings in hash tables or performing efficient search operations.

📝 Notes

The hash code generated by the GetHashCode() method is not guaranteed to be unique for distinct strings. Different strings may produce the same hash code (hash collision), although the algorithm aims to minimize collisions.
The hash code is based on the contents of the string, and any change to the string's content will result in a different hash code.

🎢 Optimization

The GetHashCode() method is already optimized for efficiency. It uses a well-defined algorithm to compute the hash code based on the string's content.

🎉 Conclusion

The GetHashCode() method in C# is a valuable tool for obtaining a hash code representation of a string. It plays a crucial role in scenarios where efficient data retrieval and storage are essential.

Feel free to experiment with different strings and explore how the GetHashCode() method behaves with various inputs. Happy coding!