What am I doing wrong here with find and string?

Question

I am asking user to enter date in format with slashes. Then I try to find the slashes in the string using find. I get error saying I cannot compare pointer with integer on my if statement. Here is code.

// test inputing string date formats
#include <iostream>
#include <string>
#include <algorithm>

int main() {
   std::string dateString;
   int month,day,year;

   std::cout << "Enter a date in format of 5/14/1999: ";
   std::getline(std::cin,dateString);

   std::cout << "You entered " << dateString << std::endl;

   if (std::find(dateString.begin(),dateString.end(),"/") != dateString.end()) {
      std::cout << "Found slash in date.\n";
   }
   else {
      std::cout << "screwed it up.\n";
   }
}

Any help is appreciated.

@MikhailGenkin it's nothing special. *back-slash* is what you're thinking of. — WhozCraig, Oct 09 '19 at 01:13
If I were to point you to [Single quotes vs. double quotes in C or C++](https://stackoverflow.com/questions/3683602/single-quotes-vs-double-quotes-in-c-or-c), would you see that as a duplicate question? — JaMiT, Oct 09 '19 at 01:13
You should be looking for a value of element-type, where the type is decided from the iterators used. A `std::string` contains `char`. You're providing a `const char*` (eventually). They're not synonymous. Look for `'/'` , not `"/"` . — WhozCraig, Oct 09 '19 at 01:14
Unrelated: "`5/14/1999`" isn't a format. It's a point in time or an example of a date. — Ted Lyngmo, Oct 09 '19 at 03:22

score 2 · Accepted Answer · answered Oct 09 '19 at 01:20

if (std::find(dateString.begin(),dateString.end(),"/") != dateString.end()) {

"/" is a literal string, or a const char * (actually a const char[2] in this case, to be pedantic, but this is not germane) . The third parameter to std::find, in this case, should be a char, a single character.

You probably meant

if (std::find(dateString.begin(),dateString.end(),'/') != dateString.end()) {

score 1 · Answer 2 · answered Oct 09 '19 at 01:52

I think you can use

if (dateString.find("/") != std::string::npos) {
    std::cout << "Found slash in date.\n";
} else {
    std::cout << "screwed it up.\n";
}

to find substring/char in a string. Note that std::string::find() works for char, const char * and std::string.

What am I doing wrong here with find and string?

2 Answers2