Tutorials

C++ String strchr() Function

Posted in C++ Tutorial

Updated on Nov 19, 2024

By Mari Selvan

👁️ 114 - Views

⏳ 4 mins

💬 1 Comment

Photo Credit to CodeToFun

🙋 Introduction

In C++ programming, manipulating strings is a common task, and the strchr() function is a handy tool for working with null-terminated strings.

This function is part of the C Standard Library and is used to locate the first occurrence of a specified character within a string.

In this tutorial, we'll explore the usage and functionality of the strchr() function in C++.

💡 Syntax

The signature of the strchr() function is as follows:

Syntax

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char* strchr(const char* str, int character);

This function searches for the first occurrence of the specified character (an integer representing an ASCII value) within the null-terminated string str.

📄 Example

Let's delve into an example to illustrate how the strchr() function works.

strchr.cpp

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#include <iostream>
#include <cstring>

int main() {
  const char * sentence = "Hello, C++!";
  char searchChar = 'C';

  // Search for the character 'C'
  const char * result = strchr(sentence, searchChar);

  // Output the result
  if (result != nullptr) {
    std::cout << "The character '" << searchChar << "' was found at position: " << result - sentence << std::endl;
  } else {
    std::cout << "The character '" << searchChar << "' was not found in the string." << std::endl;
  }

  return 0;
}

💻 Output

Output

The character 'C' was found at position: 7

🧠 How the Program Works

In this example, the strchr() function searches for the character 'C' within the string "Hello, C++!" and prints the result.

↩️ Return Value

The strchr() function returns a pointer to the first occurrence of the specified character in the string. If the character is not found, it returns a null pointer (nullptr).

📚 Common Use Cases

The strchr() function is particularly useful when you need to locate the position of a specific character within a string. It simplifies tasks such as extracting substrings or validating the presence of certain characters.

📝 Notes

The strchr() function is case-sensitive. If you need a case-insensitive search, consider using std::string and std::find() or implement a custom case-insensitive search.
For C++ strings, the find() method provides similar functionality and is often preferred for its flexibility.

🎢 Optimization

The strchr() function is optimized for efficiency, and no additional optimization is typically needed. Ensure that you handle the possibility of a null pointer if the character is not found.

🎉 Conclusion

The strchr() function in C++ is a valuable tool for searching for a specific character within null-terminated strings. It provides a standardized and efficient way to perform this task, enhancing the flexibility and readability of your code.

Feel free to experiment with different strings and characters to explore the behavior of the strchr() function in various scenarios. Happy coding!