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What I want to do is similar to this, except that I have a more complex class (with multiple properties).

Convert a list to a string in C#

I have a class with multiple properties which is stored in a list

While populating this list, I also populate a | seperated string with the name property, which is subsequently used by regex

So, can I just populate the list, and afterwards, easily build a | seperated string from the Name property of the class in the list?

Example Code

Class being populated:

public class Thing
{
    public MyParentClass parent;
    public string Name;         
    public List<string> OtherThings = new List<string>();

    public Thing(string path)
    {
        // Here I set the Name property to the filename
        Name = Path.GetFileNameWithoutExtension(path);
    }

}

Populating code:

public List<Thing> Stuff = new List<Thing>();
public string AllThings = "";

void GetThings(files)
{
foreach (string f in files)
    {
        Stuff.Add(f)
        AllThings  = AllThings + Path.GetFileNameWithoutExtension(f) + "|";
    }
}

So what I want to know is: Can I remove the AllThings = AllThings + line and instead populate AllThings after all the classes are loaded?

If I try something like this:

AllCubes = string.Join("|", Stuff.ToArray());

I get

CS0121 The call is ambiguous between the following methods or properties: 'string.Join(string, params object[])' and 'string.Join(string, IEnumerable)'

Which is no suprise as I know it's not that simple - I just wanted to try and see

Nick.Mc
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1 Answers1

1

To make String.Join work you will need to provide a collection of strings, not a custom type.

Ambiguity is due to covariance, since it can implicitly become an object or string in this case.

So instead of your approach go ahead with explicitly stating that it will be string and pushing certain property of object as that string:

AllCubes = string.Join("|", Stuff.Select(x => x.Name));.

This will provide an IEnumerable of strings which meets contract requirements IEnumerable<string>.

Karolis Kajenas
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