Direct cast expression for input constructor when use inherit

[rootflood]

make simpler constructor when using inherit constructors

using System.IO;

    // parent
    public class DirInfo 
    {
        public DirInfo( string Name, int FilesCount, string FullName)
        {}
    }

    public class DirInfoByAddress : DirInfo // inherit ^^^
    {
        public DirInfoByAddress(string Address)  // get address and make DirectoryInfo class
            :this(new DirectoryInfo(Address)){}

        private DirInfoByAddress(DirectoryInfo Info) : // send DirectoryInfo to parent
            base(Info.Name,
                 Info.GetFiles().Length,
                 Info.FullName){}


        public DirInfoByAddress(string Address)  // use a expression for short
            :base
            {
                Info: new DirectoryInfo(Address)  // <<<
            }
                (Info.Name,
                 Info.GetFiles().Length,
                 Info.FullName){}
    }

[canton7]

I don't understand what the

            {
                Info: new DirectoryInfo(Address)  // <<<
            }

syntax does I'm afraid. Could you please add some text which explains your proposal a bit more: what problem does it solve, how does it do this, and what exactly does your new syntax compile to?

[HaloFour]

The two constructors you are currently writing seems much cleaner to me than the syntax that you're suggesting.

There are other proposals seeking to be able to run code before the call to the base constructor which could also solve your need:

    public class DirInfoByAddress : DirInfo
    {
        private DirInfoByAddress(string Address) {
            var di = new DirectoryInfo(Address);
            base(di.Name, di.GetFiles().Length, di.FullName);
        }
    }

[rootflood]

this is almost same but with one problem, this is on code block but if that was in data block can tell you can't write code here, so just data must be here
however if i can write codes before of call base constructor then its better for me
for example:

        public DirInfoByAddress(string Address)
        {
            if(Directory.Exists(Address) is false)
                Directory.CreateDirectory(Address);
            var di = new DirectoryInfo(Address);
            base(di.Name, di.GetFiles().Length, di.FullName);
        }

but i think .net have limitation for write code before of call base constructor, isn't?

[CyrusNajmabadi]

but i think .net have limitation for write code before of call base constructor, isn't?

@HaloFour is saying that there's an existing proposal which would allow you to do what you want, but in a cleaner fashion. For example, as he linked in his post: #3984

[HaloFour]

@rootflood

but i think .net have limitation for write code before of call base constructor, isn't?

The limitation .NET enforces is that you can't access this or instance members before calling the base constructor, but you can do anything else. That's how C# supports expressions as arguments to the base constructor. It's the syntax of the base constructor call that makes it awkward.

[rootflood]

i agree ,that syntax is much cleaner than my proposal

[rootflood]

#3980