Anthony Johnson - 1 year ago 101

ASP.NET (C#) Question

Currently I have this set of code and its meant to calculate factorials.

`int numberInt = int.Parse(factorialNumberTextBox.Text);`

for (int i = 1; i < numberInt; i++)

{

numberInt = numberInt * i;

}

factorialAnswerTextBox.Text = numberInt.ToString();

For some reason it doesn't work and i have no clue why. For example i will input 3 and get the answer as -458131456 which seems really strange.

Any help appreciated. Thanks

Answer Source

```
int numberInt = int.Parse(factorialNumberTextBox.Text);
int result = numberInt;
for (int i = 1; i < numberInt; i++)
{
result = result * i;
}
factorialAnswerTextBox.Text = result.ToString();
```

on a side note: this would normally NOT be the correct way to calculate factorials. You'll need a check on the input before you can begin calculation, in case your starting value is 1 or below, in that case you need to manually return 1.

On another side note: this is also a perfect example of where recursive methods can be useful.

```
int Factorial(int i)
{
if (i <= 1)
return 1;
return i * Factorial(i - 1);
}
```