The ? operator isn't working correctly instead of if/else

Question

I was trying to put the ? operator in my code instead of the usual if /else but it gave me the same result whether it's true or false?

int student_grade;
Console.WriteLine("enter the grade:");
student_grade = Console.Read();

Console.WriteLine((student_grade >= 60) ? "passed" :"failed");

Did you step through in the debugger to make sure `student_grade` actually got the correct value? — Phil M, Feb 27 '19 at 17:20
Then edit your question to include a [mcve] demonstrating the problem, complete with what input you give, and what output you get. See [ask] — Phil M, Feb 27 '19 at 17:23
What does [`Console.Read`](https://learn.microsoft.com/en-us/dotnet/api/system.console.read?view=netframework-4.7.2) return? Hint: Do you get the correct result when you enter `1`? — Kenneth K., Feb 27 '19 at 17:26
I strongly recommend you read "*[Difference between Console.Read() and Console.ReadLine()?](https://stackoverflow.com/questions/6825943/difference-between-console-read-and-console-readline)*". — Wai Ha Lee, Feb 27 '19 at 17:26

CoolBots · Accepted Answer · 2019-02-27T17:37:10.790

2

Console.Read returns an ASCII value of the first character in your input. Try your code with the letter "A" as input - result will be “passed", because the ASCII value for "A" is 65. It just so happens that numbers 0-9 have ASCII values 48-57, respectively; your code compares to 60, so the result is always the same.

Converting after the input will not work; you need to use Console.ReadLine(), and parse the input as int

edited Feb 27 '19 at 17:37

answered Feb 27 '19 at 17:26

CoolBots

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I'd suggest explaining *why* `A` will give the result it does. – Wai Ha Lee Feb 27 '19 at 17:30
1

Since .NET doesn't use ASCII, "Reads the next character from the standard input stream" means the next [`Char`](https://learn.microsoft.com/en-us/dotnet/api/system.char?view=netframework-4.7.2) value (UTF-16 code unit). UTF-16 is one of several character encodings of the [Unicode](http://www.unicode.org/charts/nameslist/index.html) character set. Unicode "A" (U+0041) is encoded by UTF-16 as `'\u0041'`, which has the decimal value of 65. – Tom Blodget Feb 28 '19 at 00:44

The ? operator isn't working correctly instead of if/else

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