How to convert one list to multidimensional array?

BKS Saha

8y13.1kVisual Basic .NET

public JsonResult AllListofMainDivisionDesignation() {
List designation = new List();
var designationgroup = db.HrDesignationGroup.Where(p=>p.Rank==2).ToList();
foreach (var des in designationgroup)
{ var desig = db.HrDesignation.Where(i=> i.DesignationGroupId == des.DesignationGroupId).OrderBy(r => r.Rank).ToList();
designation.AddRange(desig);}
HrDesignation[][] arrays = designation.Select(a =>a.ToArray()).ToArray();
return Json(arrays, JsonRequestBehavior.AllowGet);
}

8 Replies

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BKS Saha8y ago
Thank you sir
Nikunj Satasiya
Nikunj Satasiya8y ago
Ok Don't warry we will try another way. i will create demo for you and sand you new code soon as possible.
BKS Saha8y ago
Nikunj Satasiya sir,
I have already used similar things....but it is not working
Nikunj Satasiya8y ago
I can see there are 3 solution for it .

1. Try this
HrDesignation[][] arrays = designation.Select(a =>a.ToArray());
instad of
HrDesignation[][] arrays = designation.Select(a =>a.ToArray()).ToArray();
2. add namespace
using System.Linq;
3. change name of array any try again. this may help full to you.
try every case one by one. i hope it will work.
BKS Saha8y ago
Dear Nikunj Satasiya Sir,

'HrDesignation' does not contain a definition for 'ToArray' and no extension method 'ToArray' accepting a first argument of type 'HrDesignation' could be found (are you missing a using directive or an assembly reference?)
Nikunj Satasiya8y ago
can You Show me Actuall Error u getting .
BKS Saha8y ago
Thank you sir

Nikunj Satasiya

I am facing problem this line.

HrDesignation[][] arrays = designation.Select(a =>a.ToArray()).ToArray();
Nikunj Satasiya8y ago
Hi BKS Saha,

You can try this
//extension method
public static object[,] To2DArray(this IEnumerable lines, params Funcobject>[] lambdas)
{
  var array = new object[lines.Count(), lambdas.Count()];
  var lineCounter = 0;
  lines.ForEach(line =>
  {
    for (var i = 0; i < lambdas.Length; i++)
    {
      array[lineCounter, i] = lambdas[i](line);
    }
    lineCounter++;
  });
  return array;
}

[Test]
public void Test()
{
  var lines = new List();
  lines.Add(new Line() { Id=1, Name="One", Age=25 });
  lines.Add(new Line() { Id = 2, Name = "Two", Age = 35 });
  lines.Add(new Line() { Id = 3, Name = "Three", Age = 45 });

  //Convert to 2d array
  //[1,One,25]
  //[2,Two,35]
  //[3,Three,45]
  var range = lines.To2DArray(x => x.Id, x => x.Name, x=> x.Age);

  //test the result
  for(var i=0;i
  {
    for(var j=0;j<3;j++)//3 lambdas passed to function
    {
      Console.Write(range[i,j]+",");
    }
    Console.WriteLine();
  }
}

class Line
{
  public int Id { get; set; }
  public string Name { get; set; }
  public int Age { get; set; }
}
OR Simpaly you cal also try this way.
class Program
{
    static void Main()
    {
        // A.
        // New list here.
        List<string> l = new List<string>();
        l.Add("one");
        l.Add("two");
        l.Add("three");
        l.Add("four");
        l.Add("five");

        // B.
        string[] s = l.ToArray();
    }
}