How to Trim a String in C++ - Step by Step Examples

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How to Trim a String in C++ ?

Answer

To trim a string in C++, you can create a custom function to remove leading and trailing whitespace characters.

✐ Examples

1 Trimming " Hello World "

In this example,

We create a custom function named trim that takes a string as input and removes leading and trailing whitespace characters.
We call the trim function with the string " Hello World ".
Finally, we print the trimmed string.

C++ Program

#include <iostream>
#include <algorithm>
#include <cctype>

void trim(std::string &str) {
    str.erase(0, str.find_first_not_of(' '));
    str.erase(str.find_last_not_of(' ') + 1);
}

int main() {
    std::string str = "   Hello World   ";
    trim(str);
    std::cout << "Trimmed string is: '" << str << "'\n";
    return 0;
}

Output

Trimmed string is: 'Hello World'

2 Trimming leading whitespace from " apple"

In this example,

We create a custom function named ltrim that takes a string as input and removes leading whitespace characters.
We call the ltrim function with the string " apple".
Finally, we print the trimmed string.

C++ Program

#include <iostream>
#include <algorithm>
#include <cctype>

void ltrim(std::string &str) {
    str.erase(0, str.find_first_not_of(' '));
}

int main() {
    std::string str = "   apple";
    ltrim(str);
    std::cout << "Trimmed string is: '" << str << "'\n";
    return 0;
}

Output

Trimmed string is: 'apple'

3 Trimming trailing whitespace from "banana "

In this example,

We create a custom function named rtrim that takes a string as input and removes trailing whitespace characters.
We call the rtrim function with the string "banana ".
Finally, we print the trimmed string.

C++ Program

#include <iostream>
#include <algorithm>
#include <cctype>

void rtrim(std::string &str) {
    str.erase(str.find_last_not_of(' ') + 1);
}

int main() {
    std::string str = "banana   ";
    rtrim(str);
    std::cout << "Trimmed string is: '" << str << "'\n";
    return 0;
}

Output

Trimmed string is: 'banana'

Summary

In this tutorial, we learned How to Trim a String in C++ language with well detailed examples.

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How to Trim a String in C++ - Step by Step Examples

How to Trim a String in C++ ?

Answer

✐ Examples

1 Trimming " Hello World "

C++ Program

Output

2 Trimming leading whitespace from " apple"

C++ Program

Output

3 Trimming trailing whitespace from "banana "

C++ Program

Output

Summary

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