String is a sequence of characters. In C++ programming language, The strings can be defined in two ways −
C style strings: treats the string as a character array.
String Class in C++
The string class can be used in a C++ program from the library ‘string’. It stores the string as a character array in the memory but shows it as a string object to the user. In C++ there are many methods that support the C++ string class and help in the proper function of the object and increase the efficiency of the code.
Example
Some common string application are found where string are used −
#include <bits/stdc++.h>
using namespace std;
bool charcheck(string str) {
int l = str.length();
for (int i = 0; i < l; i++) {
if (str.at(i) < '0' || str.at(i) > '9')
return false;
}
return true;
}
string replacedotWith20(string str) {
string replaceby = "%20";
int n = 0;
while ((n = str.find(" ", n)) != string::npos ) {
str.replace(n, 1, replaceby);
n += replaceby.length();
}
return str;
}
int main() {
string num = "3452i";
if (charcheck(num))
cout << "string contains only digit" << endl;
else
cout<<"string contains other characters too"<<endl;
string url = "google com in";
cout << replacedotWith20(url) << endl;
return 0;
}Output
String contains other characters too.
google%20com%20in
The above thing can be help while working with web.