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Is it possible to blow up an array so that its elements can be passed to a method with the params keyword?

Take this non-compiling code, for example:

public string GetPath(string basefolder, string[] extraFolders)
{
    string version = Versioner.GetBuildAndDotNetVersions();
    string callingModule = StackCrawler.GetCallingModuleName();
    return AppendFolders(basefolder, version, callingModule, extraFolders);
}
private string AppendFolders(params string[] folders)
{
    string outstring = folders[0];
    for (int i = 1; i < folders.Length; i++)
    {
        string fixedPath = folders[i][0] == '\\' ? folders[i].Substring(1) : folders[i];
        Path.Combine(outstring, fixedPath);
    }
    return outstring;
}

This example is a slightly simplified version of the testing code that I use. Please, I'm only interested in solutions that are directly related to the param keyword. I know how lists and other similar things work.

Is there any way to "explode" the extraFolders array so that its contents can be passed to the AppendFolders along with other parameters?

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5 answers

One parameter is to make parameter paramsa object[]:

static string appendFolders(params object[] folders)
 { return (string) folders.Aggregate("",(output, f) => 
                       Path.Combine( (string)output
                                    ,(f is string[]) 
                                      ? appendFolders((object[])f)
                                      : ((string)f).TrimStart('\\')));
 }

- , :

  static string appendFolders(params StringOrArray[] folders)
     { return folders.SelectMany(x=>x.AsEnumerable())
                     .Aggregate("",
                       (output, f)=>Path.Combine(output,f.TrimStart('\\')));
     }

   class StringOrArray
     { string[] array;

       public IEnumerable<string> AsEnumerable()
        { return soa.array;}

       public static implicit operator StringOrArray(string   s)   
        { return new StringOrArray{array=new[]{s}};}

       public static implicit operator StringOrArray(string[] s)  
        { return new StringOrArray{array=s};}
     }

:

appendFolders("base", "v1", "module", new[]{"debug","bin"});
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. - . "params" - , .

AppendFolders(extraFolders);

, , .

List<string> lstFolders = new List<string>(extraFolders);
lstFolder.Insert(0, callingModule);
lstFolder.Insert(0, version);
lstFolder.Insert(0, basefolder);
return AppendFolders(lstFolders.ToArray());
+7

"", , "". , " params" " ". , , , . ( ) :

return AppendFolders(new string[] { basefolder, version, callingModule }.Concat(extraFolders).ToArray());

:

, :

return AppendFolders(new string[] { baseFolder, callingModuleName, version }.Concat(extraFolders));

public static T[] Concat<T>(this T[] a, T[] b) {
   return ((IEnumerable<T>)a).Concat(b).ToArray();
}

, , , List <T> :

return AppendFolders(new Params<string>() { baseFolder, callingModuleName, version, extraFolders });

class Params<T> : List<T> {
    public void Add(IEnumerable<T> collection) {
       base.AddRange(collection);
    }

    public static implicit operator T[](Params<T> a) {
       return a.ToArray();
    }
}
+2

<string> , ( ToArray()).

, . Path.Combine .

+1

, OregonGhost, , , . , - :

public string GetPath(string basefolder, string[] extraFolders)
{
    string version = Versioner.GetBuildAndDotNetVersions();
    string callingModule = StackCrawler.GetCallingModuleName();

    List<string> parameters = new List<string>(extraFolders.Length + 3);
    parameters.Add(basefolder);
    parameters.Add(version);
    parameters.Add(callingModule);
    parameters.AddRange(extraFolders);
    return AppendFolders(parameters.ToArray());
}

, , , , .

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