I am currently converting what was a Console Application into a Windows Form application. Fortunatly i initially designed the application to work with a GUI in the future so there was not much code to change.
I have a UserCollection class which itself holds a List<> of type User/Member (Member is derives from User).
What i would like to do is to add each item in the UserCollection List<> to the ListView, so i can see each entry and have the multiple entries list vertically.
I have tried to implement this myself firstly by using:
private void UpdatePeopleListings()
{
foreach (User person in newCollection)
{
listViewPeople.Items.Add(person.ToString());
}
}
Where newCollection is the new object created from the UserCollection class in the main windows form.
I recieve the error:
foreach statement cannot operate on variables of type 'Collection.UserCollection' because 'Collection.UserCollection' does not contain a public definition for 'GetEnumerator'
I then tried to make a small workaround, so in my UserCollection i created the following method:
public User ReturnUser()
{
foreach (User person in _userCollection)
{
return person;
}
return null;
}
(_userCollection is the List<> of Users/Members in UserCollection.cs)
And then use it like this:
private void UpdatePeopleListings()
{
listViewPeople.Items.Add(newCollection.ReturnUser().ToString());
}
Although this does populate the ListView with an entry, it only populates the first entry. If i was to add more than one User/Member to the newCollection then it simply repeats the first entry.
How would i go about populating the ListView with ALL objects in the collection properly and how would i prevent it from repeating only one object.
UserCollecton.cs
///////////////////////////////////////////////////////////
// UserCollection.cs
// Implementation of the Class UserCollection
// Generated by Enterprise Architect
// Created on: 22-Oct-2009 22:40:30
///////////////////////////////////////////////////////////
#region Using Statements
using System;
using System.Collections.Generic;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
using System.IO;
#endregion
namespace Collection
{
//Allows the class to be saved
[Serializable()]
public class UserCollection
{
#region Fields
//Declares a list of type User (Which also holds derived Member objects)
private List<User> _userCollection = new List<User>();
//Holds number of members
int nMember = 0;
//Holds number of users
int nUser = 0;
#endregion
#region Add Operations
/// <summary>
/// Adds a new user
/// </summary>
/// <param name="user"></param>
public void AddUser(User user)
{
//Adds the user given in the operation parameters to the collection
_userCollection.Add(user);
nUser++;
//Sorts the collection using the CompareTo() specified in the User class.
_userCollection.Sort();
//Console.WriteLine used for testing purposes
//Console.WriteLine("added");
}
///<summary>
///Adds a new Member
///</summary>
/// <param name="member"></param>
public void AddMember(Member member)
{
//Adds the member given in the operation parameters to the collection
_userCollection.Add(member);
nMember++;
//Sorts the collection using the CompareTo() specified in the User class.
_userCollection.Sort();
//Console.WriteLine used for testing purposes
//Console.WriteLine("added");
}
#endregion
#region Removal Operations
///<summary>
///Removes a user based on FirstName,LastName and PostCode
///</summary>
/// <param name="person"></param>
public void RemoveUser(User person)
{
//Only search collection for users if there is data in it
if (_userCollection.Count > 0)
{
//Create a temp list for any matched found
List<User> tempList = new List<User>();
foreach (User u in _userCollection)
{
//If the details stored in the collection match the details given in the search
if (u.FName == person.FName && u.LName == person.LName && u.PostCode == person.PostCode)
{
//Add any matches to the temp list
tempList.Add(u);
}
else
{
throw new ArgumentException("User not found");
}
}
//Delete any matches
foreach (User u in tempList)
{
_userCollection.Remove(u);
//Decrement user count
nUser--;
}
}
else
{
throw new AccessViolationException("No data in collection");
}
}
/// <summary>
/// Removes a user using Membership number
/// </summary>
/// <param name="number"></param>
public void RemoveMember(int number)
{
//Create a temp list of type Member
Member temp = new Member();
//Use the temp list to compare types and store all objects of type member
//found in the collection to it.
List<User> Mems = _userCollection.FindAll(delegate(User u)
{ return u.GetType() == temp.GetType(); });
//Delete any matches
foreach (Member m in Mems)
{
if (m.mNum == number)
{
_userCollection.Remove(m);
//Decrement member count
nMember--;
}
else
{
throw new ArgumentException("Member not found");
}
}
}
#endregion
#region Search Operations
///<summary>
///Returns member by Membership number
/// </summary>
///
/// <param name="_mNumber"></param>
public Member FindByMNo(int number)
{
//Create a temp list of type Member
Member temp = new Member();
//Use the temp list to compare types and store all objects of type member
//found in the collection to it.
List<User> Mems = _userCollection.FindAll(delegate(User u)
{ return u.GetType() == temp.GetType(); });
//Return any matches found
foreach (Member i in Mems)
{
if (i.mNum == number)
{
return i;
}
}
throw new ArgumentException("Member not found");
}
///<summary>
///Returns a list of Users matching details given
///</summary>
///
/// <param name="_fName"></param>
/// <param name="_lName"></param>
public List<User> FindByName(User person)
{
//Create a temp list to store any matches
List<User> temp = new List<User>();
//Add matches found to the temp list
foreach (User u in _userCollection)
{
if (u.LName == person.LName)
{
temp.Add(u);
}
}
if (temp.Count > 0)
{
//Return the list that holds any matches
return temp;
}
throw new ArgumentException("User not found");
}
public User ReturnUser()
{
foreach (User person in _userCollection)
{
return person;
}
return null;
}
#endregion
#region Edit Operations
///<summary>
///Edits a members membership expiry
///</summary>
///
/// <param name="member"></param>
public void EditMemStatus(int member, DateTime newDate)
{
//Create a temp list of type Member
Member temp = new Member();
//Use the temp list to compare types and store all objects of type member
//found in the collection to it.
List<User> Mems = _userCollection.FindAll(delegate(User u)
{ return u.GetType() == temp.GetType(); });
//Search for the member that matches the number given in the parameter
foreach (Member m in Mems)
{
if (m.mNum == member)
{
//Replace the match with the new expiry
m.mExp = newDate;
}
else
{
throw new ArgumentException("Date cannot be changed");
}
}
}
#endregion
#region I/O Operations
public bool SaveData()
{
try
{
//Open the stream using the Data.txt file
using (Stream stream = File.Open("Data.txt", FileMode.Create))
{
//Create a new formatter
BinaryFormatter bin = new BinaryFormatter();
//Copy data in collection to the file specified earlier
bin.Serialize(stream, _userCollection);
bin.Serialize(stream, nMember);
bin.Serialize(stream, nUser);
//Close stream to release any resources used
stream.Close();
}
return true;
}
catch (IOException ex)
{
throw new ArgumentException(ex.ToString());
}
}
public bool LoadData()
{
//Check if file exsists, otherwise skip
if (File.Exists("Data.txt"))
{
try
{
using (Stream stream = File.Open("Data.txt", FileMode.Open))
{
BinaryFormatter bin = new BinaryFormatter();
//Copy data back into collection fields
_userCollection = (List<User>)bin.Deserialize(stream);
nMember = (int)bin.Deserialize(stream);
nUser = (int)bin.Deserialize(stream);
stream.Close();
//Sort data to ensure it is ordered correctly after being loaded
_userCollection.Sort();
return true;
}
}
catch (IOException ex)
{
throw new ArgumentException(ex.ToString());
}
}
else
{
//Console.WriteLine present for testing purposes
Console.WriteLine("\nLoad failed, Data.txt not found");
return false;
}
}
#endregion
#region Properties
//Gets amount of Members in collection
public int GetNMember
{
get
{
return nMember;
}
}
//Gets amount of Users in collectioj
public int GetNUser
{
get
{
return nUser;
}
}
#endregion
}//end UserCollection
}
Ignore any random Console stuff, i've not finished the cleanup yet.
Thanks for the help!