conditional (ternary) operator using C#

cjo · November 4th, 2003, 01:54 PM

Friends,

I'm attempting to use the following method in a class. "altitude" is a member of the class with ushort data type.

public void Descend()
{
altitude >= 5000 ? altitude -= 5000 : altitude = 0;
}

However, I'm getting the following error message specifically referencing the line of code above: Compiler Error Message: CS0201: Only assignment, call, increment, decrement, and new object expressions can be used as a statement

Apparently I can't use a conditional operator as a statement, but when I remove the semicolon, I get a different error message telling me that a semicolon is expected.

Is my syntax incorrect or am I using this conditional operator incorrectly?

Thanks in advance for any help you can provide.

planoie · November 4th, 2003, 03:01 PM

Well, it looks like it's having an issue with "-=". That isn't an assignment, call, increment, decrement, and new object expression.

Peter
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Work smarter, not harder.

cjo · November 4th, 2003, 03:06 PM

Nevermind. I think I got it:

public void Descend()
{
altitude = altitude >= 500 ? (ushort)(altitude - 5000) : (ushort)0;
}

This works. If I had you thinking about it ... thanks any.

katzman · January 12th, 2005, 11:55 AM

would this work? (i tested in java--never used c#--and it works fine, but there might be some nuances.

Code:

// if altitude is more than 5000, decrement it by 5000
// if it is less than 5000, decrement it by its own value
// hence setting it to zero

altitude -= (altitude >= 5000) ? 5000 : altitude;

slightly more terse...oh well.

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also, i realize this thread is over a year old, but alas...bless google for bringing me to it.