This is a text-only version of the following page on https://raymii.org:
---
Title       : 	C++ Remove leading or trailing characters from std::string
Author      : 	Remy van Elst
Date        : 	18-07-2020
URL         : 	https://raymii.org/s/snippets/Cpp_Remove_leading_or_trailing_characters_from_string.html
Format      : 	Markdown/HTML
---



Here's a small snippet to remove leading or trailing characters
from a std::string in C++. I use it to strip leading and trailing zeroes 
in a game score display function.

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### Code

These are the two functions, one to remove leading zeroes and one to remove trailing 
zeroes:

	static void removeTrailingCharacters(std::string &str, const char charToRemove) {
	    str.erase (str.find_last_not_of(charToRemove) + 1, std::string::npos );
	}

	static void removeLeadingCharacters(std::string &str, const char charToRemove) {
	    str.erase(0, std::min(str.find_first_not_of(charToRemove), str.size() - 1));
	}

### Usage example

Example program and output:

	#include <iostream>
	#include <string>

	static void removeTrailingCharacters(std::string &str, const char charToRemove) {
	    str.erase (str.find_last_not_of(charToRemove) + 1, std::string::npos );
	}

	static void removeLeadingCharacters(std::string &str, const char charToRemove) {
	    str.erase(0, std::min(str.find_first_not_of(charToRemove), str.size() - 1));
	}

	int main() {
	    std::string example1 = "0000abc000";
	    std::cout << "before trailing removal: " << example1 << std::endl;
	    removeTrailingCharacters(example1, '0');
	    std::cout << "after trailing removal:  " << example1 << std::endl;
	    std::cout << std::endl;
	    std::cout << "before leading removal:  " << example1 << std::endl;
	    removeLeadingCharacters(example1, '0');
	    std::cout << "after leading removal:   " << example1 << std::endl;

	    return 0;
	}


Output:

	before trailing removal: 0000abc000
	after trailing removal:  0000abc

	before leading removal:  0000abc
	after leading removal:   abc




---

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