How to convert string to float in cpp [duplicate]

manpreet Best Answer 2 years ago

I want to convert string to float. I used the function std::atof, but when i have a string of zero this does not work because the return number of std::atof is 0 if it was succesful. Some of the strings are not numbers. There for, with this code i wrote:

  float att_valur_converted;
        att_valur_converted = std::atof(m_pAttr->att_value);
        if (att_valur_converted != 0.0){      
        sprintf(m_pAttr->att_value,"%.2f", att_valur_converted);

This will not work for zero. What can I do so this will work for zero? Thanks.

manpreet 2 years ago

double f = 0.0;    
std::f="https://forum.tuteehub.com/tag/string">stringstream ss;
std::f="https://forum.tuteehub.com/tag/string">string s = "213.1415";    
ss << s;
ss >> f;  //f now contains the converted f="https://forum.tuteehub.com/tag/string">string into a double  
f="https://forum.tuteehub.com/tag/cout">cout << f;