cannot implicitly convert type 'object' to 'system.guid'? An Explicit conversion exists (are you missing a cast?) error

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My Controller
Hi I got cannot implicitly convert type object to system.guid? An Explicit conversion exists (are you missing a cast?) error in this line taxinfotaxfiled.TaxFieldID = i.Value; Especially in "i" I gave "Value" (i.Value) but still showing same error. please any one suggest me the solution?

C#

public ActionResult Create(TaxInfoTaxFiled taxinfotaxfiled)
        {
           ArrayList Alist = new ArrayList();
            {
                Alist.Add("FD713788-B5AE-49FF-8B2C-F311B9CB0CC4");
                Alist.Add("FD713788-B5AE-49FF-8B2C-F311B9CB0CC4");
                Alist.Add("64B512E7-46AE-4989-A049-A446118099C4");
                Alist.Add("376D45C8-659D-4ACE-B249-CFBF4F231915");
                Alist.Add("59A2449A-C5C6-45B5-AA00-F535D83AD48B");
                Alist.Add("03ADA903-D09A-4F53-8B67-7347A08EDAB1");
                Alist.Add("2F405521-06A0-427C-B9A3-56B8931CFC57");
            }

            if (ModelState.IsValid)
            {
                taxinfotaxfiled.TaxInfoTaxFieldID = Guid.NewGuid();

                foreach (var i in Alist)
                {
                    taxinfotaxfiled.TaxFieldID = i.Value;
                   }

                db.TaxInfoTaxFileds.Add(taxinfotaxfiled);
                db.SaveChanges();
                return RedirectToAction("Index");
            }

return View(taxinfotaxfiled);
        }

My Model

C#

public partial class TaxInfoTaxFiled
    {
        public System.Guid TaxInfoTaxFieldID { get; set; }
        public Nullable<System.Guid> TaxInfoID { get; set; }
        public Nullable<System.Guid> TaxFieldID { get; set; }
        public Nullable<System.Guid> FieldTypeID { get; set; }
        public string FieldValue { get; set; }
}
  public partial class TaxField
    {
        public System.Guid TaxFieldID { get; set; }
        public string DisplayName { get; set; }
        public string PrintName { get; set; }
}

Posted 6-Dec-15 17:57pm

Member 12087373

Updated 6-Dec-15 18:16pm

PIEBALDconsult

v2

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Dave Kreskowiak · Answer 1 · 2015-12-06T18:10:00

Why are you even bothering with ArrayList? It's pretty old and just about every piece of code that uses it can use a List<t> in its place.

The reason you get the error is because ArrayList always returns an Object, not necessarily the type you put in. In your case, a string that looks like a GUID. Replace the ArrayList with a List<guid> and you'll solve the problem.

List<guid> AList = new List<guid>();
AList.Add(new Guid("FD713788-B5AE-49FF-8B2C-F311B9CB0CC4"));
AList.Add(new Guid("64B512E7-46AE-4989-A049-A446118099C4"));
...</guid></guid>

F-ES Sitecore · Answer 2 · 2015-12-06T22:15:00

To answer the question, arraylist can contain anything so you are adding strings (the string could be represented as a GUID, but that's irrelevant, the string could contain "Hello world") which are stored as object references. To get the original type back you need to cast the object in the arraylist to whatever type it was when added, so you would need to cast it to a string. Once back as a string you need to use Guid.Parse (or TryParse) to create a GUID from the data that is in the string. So your code should be like this;

C#

foreach (var i in Alist)
{
    taxinfotaxfiled.TaxFieldID = Guid.Parse((string)i);
}

An alternative would be to store GUIDs in the ArrayList so you don't need to bother parsing;

C#

ArrayList Alist = new ArrayList();
{
    Alist.Add(new Guid("FD713788-B5AE-49FF-8B2C-F311B9CB0CC4"));
    Alist.Add(new Guid("FD713788-B5AE-49FF-8B2C-F311B9CB0CC4"));
    // ....
}

foreach (var i in Alist)
{
    taxinfotaxfiled.TaxFieldID = (Guid)i;
}

As the other solution suggests, though, it is far better to use typed List objects like List<Guid> as ArrayList is old from before generics came along and let us do this stuff strongly-typed.

The next issue is that you're looping through each item in the arraylist and overwriting the TaxFieldID property with each item, so the overall effect is that the TaxFieldID is going to be the last value in the list, so that probably isn't the behaviour you are expecting.

cannot implicitly convert type 'object' to 'system.guid'? An Explicit conversion exists (are you missing a cast?) error

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