Thread: deleting parts of a string

I'm trying to get my program to go through the string typed in by the user and strip it of EVERYTHING but the numbers. I can't place my finger on what I'm missing. Help please?

Code:

#include<iostream>
#include<string>
using namespace std ;

int main()
{
	string myString ;

	cout << "Please enter string/numbers: " ;
	
	getline( cin, myString ) ;

	// disgard anything that's not an int
	for ( int x = 0 ; x < 10 ; x++ )
	if ( !isdigit( myString[ x ] ) )
		myString.erase( x, 1 ) ;

	// display contents
	cout << myString << endl ;
} // end main

That's another thing... when I make the number greater than 10 (say 15) I get an error when I try to enter anything into the program at runtime...

Hmmm... I tried the .length as you suggested, but still get the runtime error... I'm trying to make sure that the user doesn't enter any data other than numbers.

Code:

#include<iostream>
#include<string>
using namespace std ;

int main()
{
	string myString ;

	cout << "Please enter string/numbers: " ;
	
	getline( cin, myString ) ;

	// disgard anything that's not an int
	for ( int x = 0 ; myString.length() ; x++ )
	if ( !isdigit( myString[ x ] ) )
		myString.erase( x, 1 ) ;

	// display contents
	cout << myString << endl ;
} // end main