String to int c++ Code Example - Coding

convert string to number c++

#include <iostream>
#include <sstream>
using namespace std;
int main()
{
	string str = "123456";
 	int n;
  	stringstream ( str ) >> n;
	cout << n; //Output:123456
	return 0;
}

string to number in c++

// For C++11 and later versions
string str1 = "45"; 
string str2 = "3.14159"; 
string str3 = "31337 geek"; 

int myint1 = stoi(str1); 
int myint2 = stoi(str2); 
int myint3 = stoi(str3); 

// Output
stoi("45") is 45
stoi("3.14159") is 3
stoi("31337 geek") is 31337

string to int in c++

#include <iostream>
#include <string>
using namespace std;
int main() {
 
    string s = "10";
 
    try
    {
        int i = stoi(s);
        cout << i << '\n';
    }
    catch (invalid_argument const &e)
    {
        cout << "Bad input: std::invalid_argument thrown" << '\n';
    }
    catch (out_of_range const &e)
    {
        cout << "Integer overflow: std::out_of_range thrown" << '\n';
    }
 
    return 0;
}

Source: www.techiedelight.com

how to string to integer in c++

#include<string>
string str1 = "45"; 
string str2 = "3.14159"; 
string str3 = "31337 geek";

int myint1 = stoi(str1);
std::cout<<stoi(str1);

string to int c++

#include <iostream>
#include <string>

// namespace because why not
namespace dstd
{
    int StringtoInt(std::string str)
    {
        int multiplier = 1;
        int sum = 0;
        for(int i = str.size() - 1;i >= 0; i--)
        {
            switch(str[i])
            {
                case '0':
                sum += 0;
                break;
                case '1':
                sum += 1 * multiplier;
                break;
                case '2':
                sum += 2 * multiplier;
                break;
                case '3':
                sum += 3 * multiplier;
                break;
                case '4':
                sum += 4 * multiplier;
                break;
                case '5':
                sum += 5 * multiplier;
                break;
                case '6':
                sum += 6 * multiplier;
                break;
                case '7':
                sum += 7 * multiplier;
                break;
                case '8':
                sum += 8 * multiplier;
                break;
                case '9':
                sum += 9 * multiplier;
                break;
                case '-':
                sum *= -1;
                break;
                case ' ':
                continue;
                case 
            }
            multiplier *= 10;
        }

        return sum;
    }
}

int main()
{
  //just an example of how to use the function
    int a = dstd::StringtoInt("1992");
  	std::cout<<a<<'\n';
}

string to int c++

// Both functions work identically though you'll need to use "#include <string>" 
atoi( str.c_str() );
stoi( str );

Source: stackoverflow.com

Cpp

Related
convert integer to string c++ Code Example
memcpy c++ usage Code Example
how to iterate throguh a string in c++ Code Example
number to binary string c++ Code Example
bit c++ Code Example

Type:	Code Example
Category:	Coding
Sub Category:	Code Example
Uploaded by:	Admin
Views:	8