? : Operator

[Lost User]

Hi , have a good day Can anyone Explain for me what the meaning of this ?

a = b == null ? null : a.ToString();

P.S : for more information : I use this component Example Code , and I need to understand it ! http://www.gemboxsoftware.com/help/html/M_GemBox_Spreadsheet_ExcelWorksheet_ExtractToDataTable.htm[^]

if (e.ErrorID == ExtractDataError.WrongType)
{
e.DataTableValue = e.ExcelValue == null ? null : e.ExcelValue.ToString();
e.Action = ExtractDataEventAction.Continue;
}

Please , Don't tell to Ask at Component Forum , due my question is C# syntax things thank you

I know nothing , I know nothing ...

[Luc Pattyn]

everything you should know about C# is in your C# book, in MSDN, in the C# specification[^], etc. :|

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

[Lost User]

It means

if (b == null)
a = null;
else
a = a.ToString(); //this rarely makes sense, didn't you mean b.ToString()?

But it's an expression instead of a statement.

[Lost User]

Thank you so much , for this fast , great replay of yours , you saved me from headache :doh: I have voted for you :rose:

I know nothing , I know nothing ...

[Lost User]

Thank you , But for a certain things MSDN is Yak ! http://msdn.microsoft.com/en-us/library/ty67wk28.aspx[^] The conditional operator is right-associative. The expression a ? b : c ? d : e is evaluated as a ? b : (c ? d : e), not as (a ? b : c) ? d : e. The conditional operator cannot be overloaded. X|

I know nothing , I know nothing ...

[Lost User]

And yes I meant b.toString(); :)

I know nothing , I know nothing ...

[Lost User]

Thanks :thumbsup:

[Roger Wright]

You're right, and that's classic Microsoft - technically accurate, entirely useless information! :laugh:

"A Journey of a Thousand Rest Stops Begins with a Single Movement"

[Luc Pattyn]

"you're in an airplane" kind of stuff? :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

[Roger Wright]

Exactly! :-D

"A Journey of a Thousand Rest Stops Begins with a Single Movement"

[Lost User]

Where is the Yak point? In all fairness, the first line of the document states;

The conditional operator (?:) returns one of two values depending on the value of a Boolean expression.

Perfect logical KISS.

I are Troll :suss:

[dan sh]

I do not understand why you think like that.

[dan sh]

I guess you meant b.ToString there. If you did, you really don't need ternary operator. Convert.ToString would be enough.

[yu jian]

a = b == null ? null : a.ToString(); Means if b equals null then set a = null else set a = a.ToString() if code changed to following, I may understand it. if (b == null) { a = null; } else { a = a.toString() }

[brunoseixas]

? operator its like a IF-result statement. look:

int x = 0;
int y = 1;

if(x > y) ? y++ : y--;

If x>y = true, y++.
If x>y = false, y--;