What is the advantage of using try {} catch {} versus if {} else {}

Question

I am switching from plain mysql in php to PDO and I have noticed that the common way to test for errors is using a try / catch combination instead of if / else combinations.

Answer 1

TRY/ CATCH can be used within the programming context where you have very little information about the error or you think that might can occur such as.

#include 
using namespace std;

int main (){
    try{
        while(true){
            new int[100000];
        }
    }
    catch(bad_alloc& e){
       cout << e.what() << endl;
     }
 }

Although there are no semantic or compile-time errors in the program, but it's understandable that it posses a run-time error which is "bad_alloc" which appears when you try to continuously allocate the memory and your program run out of memory. This exception is defined in bad_alloc standard class which is a child-class of class "Exception", since it throws an implicit exception, throw keyword is not implied here.

You can also use try/catch to check if the file is accidentally deleted and can use if/else to check if there exists a file or not, both have their own advantages.