public abstract class MyBase
{
public abstract void MyFunction1(Param1 parameter, DataRow Row, long lineNo)
etc etc
}
in an abstract class.
I call this as follows
MyFunction1(param, row, LineNo)
How can i give this an optional parameter.
Also , there are many other classes that inherit from the base class above (MyBase) and make use of the MyFunction1 call, so does that mean I have to give all those methods optional parameters as well ?
You'll have to keep using the same signature declaration but your abstract method can use non optional parameters while the concrete version uses optional parameters (which means they get a default value if don't pass explicitely
a value) ie you can do:
abstract class DemoBase
{
public abstract void Test(int i); // non optional
}
class Demo : DemoBase
{
public override void Test(int i=10) // 10 if no value passed explicitely
{
Console.WriteLine(i);
}
}
and use later just MyDemo.Test(); or MyDemo.Test(5);
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How can i give an optional parameter to an abstract procedure ?
Jul 23, 2019 05:45 AM|robby32|LINK
Hi I have the following:
a definition as follows:
public abstract class MyBase
{
public abstract void MyFunction1(Param1 parameter, DataRow Row, long lineNo)
etc etc
}
in an abstract class.
I call this as follows
MyFunction1(param, row, LineNo)
How can i give this an optional parameter.
Also , there are many other classes that inherit from the base class above (MyBase) and make use of the MyFunction1 call, so does that mean I have to give all those methods optional parameters as well ?
Thanks
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Re: How can i give an optional parameter to an abstract procedure ?
Jul 23, 2019 07:04 AM|Mikesdotnetting|LINK
You can't specify an optional parameter in an abstract method. What you can do is to provide an overload that takes the "optional" parameter:
public abstract void MyFunction1(Param1 parameter, DataRow Row, long lineNo, string optional){}Inherited classes will have to provide implementations for both methods, of course.
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Re: How can i give an optional parameter to an abstract procedure ?
Jul 23, 2019 07:41 AM|PatriceSc|LINK
Hi,
You can use int lineNo=0 as usual: https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/named-and-optional-arguments#optional-arguments
You'll have to keep using the same signature declaration but your abstract method can use non optional parameters while the concrete version uses optional parameters (which means they get a default value if don't pass explicitely a value) ie you can do:
abstract class DemoBase { public abstract void Test(int i); // non optional } class Demo : DemoBase { public override void Test(int i=10) // 10 if no value passed explicitely { Console.WriteLine(i); } } and use later just MyDemo.Test(); or MyDemo.Test(5);