Thread: Validating 'phone number

Im trying to loop through an array (held inside a structure) to see if it only contains 0,1,2,3,4,5,6,7,8,9 (or a space). This is to check it is a telephone number.

Code:

do
	{
	cout<<"Telephone Number: ";
    cin.getline(mems[total_members+1].tel_num,sizeof(mems[total_members+1].tel_num),'\n');  
    tel_wrong = 0;	
	for(counter=0;counter<13;counter++)
		{
	    
		if(mems[total_members+1].tel_num[counter] != ' ' ||   mems[total_members+1].tel_num[counter] != '0' ||
                  mems[total_members+1].tel_num[counter] != '1' || 
                  mems[total_members+1].tel_num[counter] != '2' || 
                  mems[total_members+1].tel_num[counter] != '3' || 
                  mems[total_members+1].tel_num[counter] != '4' || 
                 mems[total_members+1].tel_num[counter] != '5' || 
                 mems[total_members+1].tel_num[counter] != '6' || 
                 mems[total_members+1].tel_num[counter] != '7' || 
                 mems[total_members+1].tel_num[counter] != '8' || 
                 mems[total_members+1].tel_num[counter] != '9') tel_wrong = 1;
		}
	}
	while(tel_wrong == 1);

even when I put in a valid phone number it still asks me to enter it again!

Code:

#include <iostream>
#include <stdlib.h>
#include <fstream>
#include <string.h>

using namespace std;


int main()
{
    char text[81];
    cout<<"Enter string:";
    cin.getline(text,81);
    
    char numbers[12]= {" 0123456789"};
   
    int size_of=strlen(text);
    
    
   
    
    
    
    //loop through each array to check for validity
    
   
    int counter=0;
    
    for (int a=0; a<size_of; a++)
    {
       for (int b=0; b<11; b++)
       {
           if (text[a]==numbers[b])
           {   
               counter++;
           }
       }
    } 
                  
   if (counter==size_of)
   {   
       cout<<"Contains only numbers therefore valid";
       
   }    
   
    else 
    cout<<"Contains letters therefore invalid";
     
        
    
    
    
    
    
    
    int stop;
    cin>>stop;


}

I hope this helps!

Thanks,

ive tried this:

Code:

int test=0;
	int tel_wrong=0;
	do
	{
	cout<<"Telephone Number: ";
    cin.getline(mems[total_members+1].tel_num,sizeof(mems[total_members+1].tel_num),'\n');  

	for(counter=0;counter<13;counter++)
		{

		test=isdigit(mems[total_members+1].tel_num[counter]);
		test=isspace(mems[total_members+1].tel_num[counter]);
		if(test==0)tel_wrong=1;
		}

		
	}
	while(tel_wrong == 1);

But it still wont accept even a valid phone number!

ive tried adding extra variables:

Code:

int test=0;
	int test2=0;
	int tel_wrong=0;
	int tel_wrong2=0;
	do
	{
	cout<<"Telephone Number: ";
    cin.getline(mems[total_members+1].tel_num,sizeof(mems[total_members+1].tel_num),'\n');  
	for(counter=0;counter<13;counter++)
		{

		test=isdigit(mems[total_members+1].tel_num[counter]);
		test2=isspace(mems[total_members+1].tel_num[counter]);
		if(test==0)tel_wrong=1;
		if(test2==0)tel_wrong2=1;
		}

		
	}
	while(tel_wrong == 1 || tel_wrong2 == 1);

but still doesnt work.

You're checking if the current place is a space, and if it isn't you're setting tel_wrong2 to 1.
Then you're checking the current is place is a digit, and if it is't you're setting tel_wrong to 1.

Since there are no characters which is a space and a number at the same time, you will always get a "wrong" number.

try this instead:

Code:

if(!isdigit(mems[total_members+1].tel_num[counter]) && 
   !isspace(mems[total_members+1].tel_num[counter]))
   tel_wrong = 1;

Originally Posted by FlyingDutchMan

You're checking if the current place is a space, and if it isn't you're setting tel_wrong2 to 1.
Then you're checking the current is place is a digit, and if it is't you're setting tel_wrong to 1.

Since there are no characters which is a space and a number at the same time, you will always get a "wrong" number.

try this instead:

Code:

if(!isdigit(mems[total_members+1].tel_num[counter]) && 
   !isspace(mems[total_members+1].tel_num[counter]))
   tel_wrong = 1;

Thanks that helped