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Can C++ switch case use string?
2023-07-04 07:41:08 深夜i     --     --
C++ switch case string

C++ is a powerful programming language that allows developers to create complex applications for various platforms. One of the most fundamental concepts in C++ programming is control statements, such as if-else statements, while loops, and switch-case statements. Like other programming languages, the switch-case statement in C++ is used to compare a variable or an expression with a series of values and perform different actions based on the matching result. But can you use strings in a C++ switch-case statement?

The short answer is yes, you can use strings in a C++ switch-case statement, but there are limitations. In earlier versions of C++, switch-case statements could only be used with integral expressions, such as integer or character values. However, the C++11 standard introduced a new feature called 'constexpr string literals' that allows developers to use strings in switch-case statements.

To use strings in a switch-case statement, you need to declare the string as a constexpr to ensure that it's a compile-time constant. Then, you can use the switch-case statement to evaluate the string and perform different actions based on the matching result. Here's an example of how to use strings in a switch-case statement in C++:



#include <iostream>


using namespace std;


int main() {


  constexpr char* fruit = "apple";


  


  switch (*fruit) 'b'


  


  return 0;


}

In this example, the string "apple" is declared as a constexpr and used in the switch-case statement to compare the first character of the string with the cases. If the first character of the string is 'a', 'b', or 'c', the corresponding action is performed. Otherwise, the default action is performed.

However, there are some limitations to using strings in switch-case statements in C++. First, the string must be declared as a constexpr, which means you can only use compile-time constant strings. Second, you can only compare the first character of the string in the switch-case statement, which limits the flexibility of using strings.

In conclusion, while C++ switch-case statements can use strings, it's important to understand the limitations and use them carefully. If you need to perform more complex evaluations using strings, consider using if-else statements or other control statements.

  
  

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