Converting a numerical value to a string and vice-versa

amrith92

These functions, to some, may seem trivial, but many people have queried in the forums on this topic numerous times.

The functions are templated, so that it can accommodate any data-type that the user wishes to use (For example, the same function can be used for converting variables of type long , int , double etc into strings, and vice-versa).

The first function, Fn I ( convertToString ), is capable of converting a variable of any data-type into a string.
Sample Function Call:

string MyInt = convertToString<int>(10);

The second function, Fn II ( convertFromString ), can convert a string into a variable of any data-type.
Sample Function Call:

int MyNumber = convertFromString<int>("45");

*Note*: You will have to include the header files - <sstream> and <string.h> for the code to work...

Hope this snippet helps....

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About the Author

I'm a student, freshly passed out of school, and waiting for college to begin, and very, very interested in programming, 'specially in C++. I also love the realm of Web Development, and enjoy animation (in-fact, I'm now taking a course on it) :D

/*
     This Function (Fn I) converts a variable of
     data-type DataType into a string
*/
template <typename DataType>
string convertToString(DataType MyValue)
{
     // Creates a Output String Stream to hold
     // the variable passed (MyValue)
     ostringstream OutStream;
    
     // Enter the variable into the stream
     OutStream << MyValue;
    
     // Return the stream as an array of
     // characters(string)
     return (OutStream.str());
}

/*
     This Function (Fn II) converts a string into
     a variable of data-type DataType
*/
template <typename DataType>
DataType convertFromString(string MyString)
{
     // Stores the return value
     DataType retValue;
    
     // Creates an Input String Stream to extract
     // the contents of the string
     istringstream InStream(MyString);
    
     // Read contents of String and store in retValue
     InStream >> retValue;
    
     // Return the value in the desired DataType
     return retValue;
}
William Hemsworth 1,339 Posting Virtuoso

Good simple snippet :)

amrith92 119 Junior Poster

Thanks :)

mvmalderen 2,072 Postaholic

And it's well commented and it addresses a common beginner's problem :)
Though I'm not so sure about the <string.h> you've to include, it has to be <string>, string.h contains several functions which operate on c-strings ...

Nice snippet!

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