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Why is ANTLR C# autogenerated parser not matching EOF?

I have a very simple grammar that (I think) should only allow additions of two elements like 1+1 or 2+3
grammar dumbCalculator;
expression: simple_add EOF;
simple_add: INT ADD INT;
INT:('0'..'9');
ADD : '+';
I generate my C# classes using the official ANTLR jar file
java -jar "antlr-4.9-complete.jar" C:\Users\Me\source\repos\ConsoleApp2\ConsoleApp2\dumbCalculator.g4 -o C:\Users\Me\source\repos\ConsoleApp2\ConsoleApp2\Dumb -Dlanguage=CSharp -no-listener -visitor
No matter what I try, the parser keeps adding the trailing elements although they shouldn't be allowed.
For example "1+1+1" gets parsed properly as an AST :
expression
simple_add
1
+
1
+
1
Although I specifically wrote that expression must be simple_add then EOF and simple_add is just INT ADD INT. I have no idea why the rest is being accepted, I expect ANTLR to throw an exception on this.
This is how I test my parser :
var inputStream = new AntlrInputStream("1+1+1");
var lexer = new dumbCalculatorLexer(inputStream);
lexer.RemoveErrorListeners();
lexer.AddErrorListener(new ThrowExceptionErrorListener());
var commonTokenStream = new CommonTokenStream(lexer);
var parser = new dumbCalculatorParser(commonTokenStream);
parser.RemoveErrorListeners();
parser.AddErrorListener(new ThrowExceptionErrorListener());
var ex = parser.expression();
ExploreAST(ex);
Why is the rest of the output being accepted ?

Classical scenario, I find my error 5 minutes after posting on Stack Overflow.
For anyone encountering a similar scenario, this happened because I did not explicitly set the ErrorHandler on my parser.
Naively, I expected all the AddErrorListener to handle the errors, but somehow there's a specific thing to do if you need the errors to be handled before visiting the tree.
I needed to add
parser.ErrorHandler = new BailErrorStrategy();
After this, I indeed got the exceptions on wrong input strings.
This is probably not the right thing to do, I'll let someone who knows ANTLR better to comment on this.

UiPath: How to set default values to a String[] variable

I have an exception when I'm trying to launch my workflow. It cames from my array declaration where I apparently don't have the right syntax.
My syntax really looks like the one used in the UiPath tuto I follow :
The tuto syntax:
My syntax:
I don't understand how I'm supposed to write the default values for a simple array of strings...
I'm only trying to pass the values in a Write Line activity, but this shows up when compiling:
If anyone can help, I'm stuck... Thanks
--- EDIT ---
The exception message is the following one:
Message: Compilation failure:
; expected Unvalid expression terms ',' ... many times...
The full results are stored in the Data property of this exception. Correct the errors of the source, then retry the load.

I found the problem: I did not instantiate the array with new String[] at the beginning. I suppose that the tutos are written using VB and not C#, which can explain the difference.

your declaration is correct maybe you have error in the loop here is a working example

C# how to get value from specific cell datagridview

i am working on C# and trying to save my datagridview to xml.
my code as follow :
writer.WriteStartElement("NamaBarang");
writer.WriteString(dgvCart.Rows[i].Cells[1].Value.ToString);
writer.WriteEndElement();
and the error occur at
writer.WriteString(dgvCart.Rows[i].Cells[1].Value.ToString);
Error 2 The best overloaded method match for
'System.Xml.XmlWriter.WriteString(string)' has some invalid
arguments C:\Users\Eric\Desktop\C#\Gridview\Gridview\Form1.cs 59 25 Gridview
and
Error 3 Argument 1: cannot convert from 'method group' to
'string' C:\Users\Eric\Desktop\C#\Gridview\Gridview\Form1.cs 59 44 Gridview
i am previously a vb user so i am having a hard time in c#
please help.

Youve forgotten to put empty brackets () after your ToString
VB isn't bothered about this but c# is- every time you want to call a method that has no arguments, you have to put empty brackets
//this is fine in VB
Dim x as String = y.ToString
//so is this
Dim x as String = y.ToString()
//in c# we insist on brackets when calling a method
string x = y.ToString();
//no brackets means "get the value of the property"
int I = mystring.Length;
Seeing something that looks like a method name, without brackets, usually means it's a property rather than a method. It can occasionally mean that the method itself is being used as an argument - a way of passing a method around as a variable, but that's beyond the scope of what we're discussing here.. Read up on delegates if you're interested.
In short, if you want to call a method in c#, it absolutely must have brackets after the name, whether there are arguments or not
Also handy to remember that when you see the error about "is a method group" it probably means you've tried to call a method but omitted the brackets.
C# is a struggle for VB people because it's essentially way more demanding that the syntax be absolutely right- you'll get used to it though, and it does help eventually!

setgraphicsAPIs is Overloaded Method match (C# Unity)

Can someone help me
PlayerSettings.SetGraphicsAPIs (BuildTarget.Android, TargetGlesGraphics.OpenGLES_2_0);
gives me this compile error :
Assets/_Developer/JEONG/Editor/BuildEditor.cs(776,18): error CS1502:
The best overloaded method match for
`UnityEditor.PlayerSettings.SetGraphicsAPIs(UnityEditor.Buil‌​dTarget,
UnityEngine.Rendering.GraphicsDeviceType[])' has some invalid
arguments
I don't know why but i follow the documentation in Unity

You should call it like that :
PlayerSettings.SetGraphicsAPIs (BuildTarget.Android, new [] { GraphicsDeviceType.OpenGLES3 });
As per the error message, the function is expecting an array of GraphicsDeviceType. Since you want only one device type, you still have to provide an array where there is one element.
Also, the value is GraphicsDeviceType.OpenGLES3 (full name with namespace : UnityEngine.Rendering.GraphicsDeviceType.OpenGLES3 ), and not TargetGlesGraphics.Whatever .
You can see in error message that it expects a value as an array of GraphicsDeviceType, so I searched the unity doc to find this :
https://docs.unity3d.com/ScriptReference/Rendering.GraphicsDeviceType.html

Thank you sir Pac but i tried this one
PlayerSettings.SetGraphicsAPIs (BuildTarget.Android, new [] {UnityEngine.Rendering.GraphicsDeviceType.OpenGLES2});
and it works . Thank you also to everyone that help me. Sorry for my bad english

Why does it compile?

var cv = (new CustomValidator()
{
ErrorMessage="Formato de telefone inválido",
ControlToValidate = "txtTelefoneIni", //<-- see the extra comma
});

Because it is legal syntax.
Really, it is.
When you're constructing an object using the object initializer syntax, you're allowed to leave a trailing comma after the last item, even if you end the initializer block there and then.
The reason behind it is probably that it makes it easier to come back and edit it later, as forgetting to add a comma after the previously-last-item is the #1 compile-time-problem with object-initializers.

It's intentional. Also works on enum members. (so it's easier to add more stuff)

Why should it not compile?
This type of syntax is legal in Python as well.

It compiles because it is valid C# syntax. You can also do the same thing with arrays
string[] meh = { "a", "b", "c", };

It is part of the C# language specification: Object initializers.

Because it's allowed.
Generally, allowing trailing comma in such forms (and actually using that "privilege") is useful so that programmers can add more items to the list without the risk of having forgotten to add comma at the end of the previous item.

Its a valid syntax in C#
lets see
var c = new List<int>() { 1, 2, 3 ,};

FWIW, it was already valid in C.
My favorite reason to use such a syntax (especially when defining enums) is that when you add an item to the list, the source control sees changes in one line only (the new one). It doesn't tag the previusly one as modified (because of added comma). Much more readable diff.
My 2-cents.