Styjun

I have a method that returns an IEnumerable<KeyValuePair<string, ArrayList>>, but some of the callers require the result of the method to be a dictionary. How can I convert the IEnumerable<KeyValuePair<string, ArrayList>> into a Dictionary<string, ArrayList> so that I can use TryGetValue?

method:

public IEnumerable<KeyValuePair<string, ArrayList>> GetComponents()

 // ...
 yield return new KeyValuePair<string, ArrayList>(t.Name, controlInformation);

caller:

Dictionary<string, ArrayList> actual = target.GetComponents();
actual.ContainsKey("something");

If you're using .NET 3.5 or .NET 4, it's easy to create the dictionary using LINQ:

Dictionary<string, ArrayList> result = target.GetComponents()
 .ToDictionary(x => x.Key, x => x.Value);

There's no such thing as an IEnumerable<T1, T2> but a KeyValuePair<TKey, TValue> is fine.

Creating a Dictionary object from Datable using IEnumerable

using System.Data;
using ..


public class SomeClass 
 //define other properties
 // ... 

 public Dictionary<string, User> ConvertToDictionaryFromDataTable(DataTable myTable, string keyColumnName)
 
 // define IEnumerable having one argument of KeyValuePair
 IEnumerable<KeyValuePair<string,User>> tableEnumerator = myTable.AsEnumerable().Select(row => 
 
 // return key value pair
 return new KeyValuePair<string,User>(row[keyColumnName].ToString(), 
 new User 
 
 UserID=row["userId"].ToString(),
 Username=row["userName"].ToString(),
 Email=row["email"].ToString(),
 RoleName=row["roleName"].ToString(),
 LastActivityDate=Convert.ToDateTime(row["lastActivityDate"]),
 CreateDate=Convert.ToDateTime(row["createDate"]),
 LastLoginDate=Convert.ToDateTime(row["lastLoginDate"]),
 IsActive=Convert.ToBoolean(row["isActive"]),
 IsLockedOut=Convert.ToBoolean(row["isLockedOut"]),
 IsApproved=Convert.ToBoolean(row["isApproved"])
 );
 );
 return tableEnumerator.ToDictionary(x => x.Key, x => x.Value);
 




public class User


 public string UserID get; set; 
 public string Username get; set; 
 public string Email get; set; 
 public string RoleName get; set; 
 public DateTime LastActivityDate get; set; 
 public DateTime CreateDate get; set; 
 public DateTime LastLoginDate get; set; 
 public bool IsActive get; set; 
 public bool IsLockedOut get; set; 
 public bool IsApproved get; set; 

// Other methods to follow..




 IEnumerable<KeyValuePair<string,User>> ieUsers = membershipUsers.AsEnumerable().Select(row =>
 
 return new KeyValuePair<string,User>(row.UserName.ToString(),
 new User
 
 Username = row.UserName.ToString(),
 Email = row.Email.ToString()
 );
 );
 allMembershipUsers = ieUsers.ToDictionary(x => x.Key, x => x.Value);
 return allMembershipUsers;
 }
}