C# Compiler Error: "Not All Code Paths Return a Value"

C# compiler error: not all code paths return a value

You're missing a return statement.

When the compiler looks at your code, it's sees a third path (the else you didn't code for) that could occur but doesn't return a value. Hence not all code paths return a value.

For my suggested fix, I put a return after your loop ends. The other obvious spot - adding an else that had a return value to the if-else-if - would break the for loop.

public static bool isTwenty(int num)
{
    for(int j = 1; j <= 20; j++)
    {
        if(num % j != 0)
        {
            return false;
        }
        else if(num % j == 0 && num == 20)
        {
            return true;
        }
    }
    return false;  //This is your missing statement
}

Not all code paths return a value although i do have returns?

Either change every break in your switch so that it is a return (if you will vary what you return based on whether the true or the false case is applied) or put a return statement at the end of your method, after your switch is finished with

The compiler isn't kidding; it really can see paths through your code that don't end in a return. You can trace them too.. follow your true case.. it can reach break, exit the switch and then have no return statement before it hits the end of the method. You might be certain that pairs will definitely always have a value but the compiler doesn't have that same level of knowledge about the program as you and it doesn't trace back to try and find evidence that pairs will always have a value.. it just sees "return statement inside a loop which is a block that might not execute, means code might not hit that return statement"

In case you're under an illusion as to what default is for, in a switch.. it is used when no other case applies. It is not "something that runs every time, regardless of whether some other case applied or not" so it can't be used as a catch all to return something if other cases didn't

If you're certain that one of your returns in the switch will be hit you can return something useless at the end of the method or better, throw an exception with a meaningful message so that in 6 months when all these "None of the switch statements returned a value in JsonToObjects, the input values were..." start appearing in the logs you have a good pointer to what is going wrong and where. Do not make your error message "this should never be hit"

Not all code paths return a value in C# console application Error Coode:CS0161

If list is empty (i.e. has no items) or is null, then the loop will not run. This means the code cannot reach any of the return statements, because they are all within the loop. In that case, there is no way for the program to know what value to return from the method. There is a "path" through the method which does not return a value.

This is an impossible situation - a non-void method must return something, so the compiler will not allow you to build and run the program until you have resolved it by adding an extra return statement at the end after the loop finishes, to cover the situation I've described.

CS0161: not all code paths return a value

The compiler can't know that on of the ifs will eventually evaluate to true. You need some default return value after the for loop, even if it's never reached in practice:

static int LowestDivisor(int x)
{
    if (x < 0)
        x *= -1;
    if (x == 0 || x == 1)
        return -1;
    for (int i = 2; i <= x; i++)
    {
        if (x % i == 0)
        {
            return i;
        }
    }
    // Should never happen...
    return x;
}

C# cannot return value 'not all code paths return a value' error

If your isOpponent variable has a value other than 1 no double is returned.

You have to add another return statement at the end of your function for the other cases.

The error message 'not all code paths return a value' means, that you don't have a return statement specified for all possible "paths" the program can take.

double calculateSpeed(double isOpponent)
{
    // Path 1 when `isOpponent == 1`
    if (isOpponent == 1)
    {
        double speedY = playerCard.Location.Y / stepY;
        return speedY;
    }

    // Path 2 when `isOpponent != 1`
    // Here is where you are missing a return statement.
}
calculateSpeed(1)

Main: not all code paths return a value

Return something at the end of Main. Like this:

public static int Main()
{
     List<DocPart> Parts = new List<DocPart>();
     var doc = new DocConfig();
     doc.Description = "bla bla";
     doc.Parts = new List<DocPart>();
     doc.Parts.Add(new DocPart { Title = "aaa", TexLine = @"\include{aaa.tex}" });
     doc.Parts.Add(new DocPart { Title = "bbb", TexLine = @"\include{bbb.tex}" });
     foreach (DocPart part in doc.Parts)
     {
           Console.WriteLine(part.Title);
           {
                 Console.ReadLine();
                 return 0;
           }
     }

     return -1;
}

---

Related Topics