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Using a Parameter to Call a Class in C#

I have got a method with a single parameter of string class that I need to use to access another class in my project.
The following will be what I want it to do. Note that this syntax gives errors.
public string getId(string name) {
string Id = name.GetId();
return Id;
}
Assuming that the user enters "Joe" as the name, one would go to the class Joe.cs, which looks like this.
public class Joe {
public string Id = 32;
public string GetId() {
return Id;
}
}
What I want to happen here is for the first method to be able to get the GetId method from Joe if Joe is entered as a parameter. How would I do this? Thank you all.

This might point you in a better direction
The idea is to have a class called User that holds user information (funnily enough)
This way you can have a list of users (not a class for each one), as such you can easily look up a user and mess with them as much as you want
public class User
{
public string UserName { get; set; }
public string FavoriteColor { get; set; }
}
public class Program
{
// A List to hold users
private static List<User> _users = new List<User>();
private static void Main(string[] args)
{
// lets add some people
_users.Add(new User() { UserName = "Bob",FavoriteColor = "Red" });
_users.Add(new User() { UserName = "Joe", FavoriteColor = "Green" });
_users.Add(new User() { UserName = "Fred", FavoriteColor = "Blue" });
// use a linq query to find someone
var user = _users.FirstOrDefault(x => x.UserName == "Bob");
// do they exist?
if (user != null)
{
// omg yay, gimme teh color!
Console.WriteLine(user.FavoriteColor);
}
}
}
Output
Red
You can take it a step further and ask the user to look up other users (what a time to be a alive!)
Console.WriteLine("Enter a user (case sensitive)");
var userName = Console.ReadLine();
var user = _users.FirstOrDefault(x => x.UserName == userName);
if (user != null)
{
Console.WriteLine(user.FavoriteColor);
}
else
{
Console.WriteLine("Game over, you failed");
}
Console.ReadLine();

You could build a Class that can contain the details you want to store, then build a Manager class that exposes public methods that can extract informations from the stored objects:
public class Friend : IComparable<Friend>
{
public Friend() { }
public int ID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public int FriendshipLevel { get; set; }
int IComparable<Friend>.CompareTo(Friend other)
{
if (other.FriendshipLevel > this.FriendshipLevel) return -1;
else return (other.FriendshipLevel == this.FriendshipLevel) ? 0 : 1;
}
}
public class MyFriends : List<Friend>
{
public MyFriends() { }
public int? GetID(string FriendName)
{
return this.Where(f => f.FirstName == FriendName).FirstOrDefault()?.ID;
}
public Friend GetFriendByID(int FriendID)
{
return this.Where(f => f.ID == FriendID).FirstOrDefault();
}
}
Build a sample class:
MyFriends myFriends = new MyFriends()
{
new Friend() { ID = 32, FirstName = "Joe", LastName = "Doe", FriendshipLevel = 100},
new Friend() { ID = 21, FirstName = "Jim", LastName = "Bull", FriendshipLevel = 10},
new Friend() { ID = 10, FirstName = "Jack", LastName = "Smith", FriendshipLevel = 50},
};
Then you can extract informations on single/multiple objects using the public methods of the "Manager" class:
int? ID = myFriends.GetID("Joe");
if (ID.HasValue) // Friend Found
Console.WriteLine(ID);
//Search a friend by ID
Friend aFriend = myFriends.GetFriendByID(32);
if (aFriend != null)
Console.WriteLine($"{aFriend.FirstName} {aFriend.LastName}");
Or you can use LINQ to get/aggregate the required informations directly if there isn't a public method that fits:
// Get your best friends using LINQ directly
List<Friend> goodFriends = myFriends.Where(f => f.FriendshipLevel > 49).ToList();
goodFriends.ForEach((f) => Console.WriteLine($"{f.FirstName} {f.LastName}"));
//Best friend
Friend bestFriend = myFriends.Max();

With respect to your Question : GetId method from Joe if Joe is entered as a
parameter.
You can achieve that in the following ways also:
2. Method Using Named Method.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Problem
{
// Simple Model Class.
public class Person
{
public int Id { get; set; }
public string Name { get; set; }
}
class Program
{
// Delegate.
public delegate string PersonHandler(Person person);
static void Main(string[] args)
{
List<Person> _persons = new List<Person>()
{
new Person(){Id=1,Name="Joe"},
new Person(){Id=2,Name="James"},
new Person(){Id=3,Name="Nick"},
new Person(){Id=4,Name="Mike"},
new Person(){Id=5,Name="John"},
};
PersonHandler _personHandler = new PersonHandler(GetIdOfPerson);
IEnumerable<string> _personIds = _persons.Select(p => _personHandler.Invoke(p));
foreach (var id in _personIds)
{
Console.WriteLine(string.Format("Id's : {0}", id));
}
}
// This is the GetId Method.
static string GetIdOfPerson(Person person)
{
string Id = person.Id.ToString();
return Id;
}
}
}
2. Method Using Anonymous Moethod.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Problem
{
// Simple Model Class.
public class Person
{
public int Id { get; set; }
public string Name { get; set; }
}
class Program
{
// Delegate.
public delegate string PersonHandler(Person person);
static void Main(string[] args)
{
List<Person> _persons = new List<Person>()
{
new Person(){Id=1,Name="Joe"},
new Person(){Id=2,Name="James"},
new Person(){Id=3,Name="Nick"},
new Person(){Id=4,Name="Mike"},
new Person(){Id=5,Name="John"},
};
PersonHandler _personHandler = delegate(Person person)
{
string id = person.Id.ToString();
return id;
};
// Retrieving all person Id's.
IEnumerable<string> _personIds = _persons.Select(p => _personHandler.Invoke(p));
foreach (var id in _personIds)
{
Console.WriteLine(string.Format("Id's : {0}", id));
}
}
}
}
2. Method Using a Lambda Expression.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Problem
{
// Simple Model Class.
public class Person
{
public int Id { get; set; }
public string Name { get; set; }
}
class Program
{
// Delegate.
public delegate string PersonHandler(Person person);
static void Main(string[] args)
{
List<Person> _persons = new List<Person>()
{
new Person(){Id=1,Name="Joe"},
new Person(){Id=2,Name="James"},
new Person(){Id=3,Name="Nick"},
new Person(){Id=4,Name="Mike"},
new Person(){Id=5,Name="John"},
};
PersonHandler _personHandler = (Person person) => person.Id.ToString();
IEnumerable<string> _personIds = _persons.Select(p => _personHandler.Invoke(p));
foreach (var id in _personIds)
{
Console.WriteLine(string.Format("Id's : {0}", id));
}
}
}
}
Output:

{get;set;} for arrayList in c# WindowsForms

Is there any solution to use set and get for arraylist ?
I want to put all of my arraylists in one class but then i need them to fill a bidimensional array to use them. (1 list=1 column)
I want to put this
ArrayList listanume = new ArrayList();
In this :
class Beneficiar
{}
And use it to fill an bidimensional array like
listanume -> a[i,0]
I really don't know how to say it right, but this is the idea...

You should do something like that
class Program
{
public static void Main(string[] args)
{
List<Account> accounts = new List<Account>();
Account a1 = new Account { Name = "Peter", Password = "lalala", Mail = "mail#yahoo.com", TotalSold = 100M };
accounts.Add(a1);
}
}
public class Account
{
public string Name { get; set; }
public string Password { get; set; }
public string Mail { get; set; }
public decimal TotalSold { get; set; }
}
To access any account by some field you can do this
string searchNameString = "Peter";
var foundAccount = accounts.FirstOrDefault(x => x.Name == searchNameString);
if (foundAccount != null)
{
//Code which uses found account
}
//Here you will get all accounts with total sold > 1000. You can then iterate over them with for or foreach
var foundAccountsByTotalSold = accounts.Where(x => x.TotalSold > 1000);

Linq GroupJoin select query

I have the following model (comments define fields within given object)
public class ServiceModel
{
public List<ShippingRequest> ShippingRequest { get; set; }
public QuotesResult QuotesResult { get; set; }
}
public class ShippingRequest
{
public Address Address { get; private set; } // AddressId
public List<ShippingPackage> ShippingPackages { get; private set; }
}
public class ShippingPackage
{
public Package Package { get; private set; } // PackageId
public List<ShippingItem> ShippingItems { get; private set; } // IsSkipped
}
public class QuotesResult
{
public List<Quote> Quotes { get; set; } // PackageId, Cost
}
Suppose I have the following input, I need to get a list of AddressId's and corresponding Quotes that refer to that address (via PackageId). Quotes are already populated at this point.
Quote.PackageId = Package.PackageId
INPUT:
Suppose I have following input with three ShippingRequests
Address1 = {Package1, Package2, Package3}
Address2 = {Package5, Package8}
Address3 = {Package11, Package12}
To get the all the quotes for a given address I need to Join PackageId of "Package" with PackageId of Quote. That way I will know that this Quote belongs to this Address.
I've tried this but i get an error:
var addrQuotes = ServiceModel.ShippingRequest
.GroupJoin(ServiceModel.QuotesResult.Quotes, c1 => c1.ShippingPackages
.SelectMany(y => y.Package.Id), c2 => c2.PackageId, (c1, c2) =>
new {
c1.Address.Id,
Quotes = c2.Select(e =>
{
e.Price = c1.ShippingPackages.Any(
x => x.ShippingItems.All(y => y.IsSkipped))
? 0
: e.Price + ExtraCost;
e.Provider = GetName(e.Code);
return e;
})
}).OrderBy(q => q.Id);
One caviar to this is that I also need to check ShippingItems(s) that go in a Package. If ALL the ShippingItems within a ShippingPackage have boolean flag "IsSkipped" set to true, the Quote's Price should be set to 0, otherwise add Extra cost to Quote.Price.
OUTPUT:
Address1 = [Quote1, Quote20, Quote21, Quote50, ...]
Address2 = [Quote3, Quote100...]
Address3 = [Quote5, Quote33, Quote12]
Any help greatly appreciated.

I didn't do entire job but got something to compile and run without errors. This should get you pointed in right direction.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
ServiceModel serviceModel = new ServiceModel()
{
ShippingRequest = new List<ShippingRequest>(){
new ShippingRequest() {
Address = "Address 1",
ShippingPackages = new List<ShippingPackage>() {
new ShippingPackage() { Package = "Package1"},
new ShippingPackage() { Package = "Package2"},
new ShippingPackage() { Package = "Package3"}
}
},
new ShippingRequest() {
Address = "Address 2",
ShippingPackages = new List<ShippingPackage>() {
new ShippingPackage() { Package = "Package5"},
new ShippingPackage() { Package = "Package8"},
}
},
new ShippingRequest() {
Address = "Address 3",
ShippingPackages = new List<ShippingPackage>() {
new ShippingPackage() { Package = "Package11"},
new ShippingPackage() { Package = "Package12"},
}
}
},
QuotesResult = new QuotesResult()
{
Quotes = new List<Quote>() {
new Quote() { Cost = 123, Id = "Package1"},
new Quote() { Cost = 123, Id = "Package2"},
new Quote() { Cost = 123, Id = "Package3"},
new Quote() { Cost = 123, Id = "Package11"},
new Quote() { Cost = 123, Id = "Package11"}
}
}
};
var addrQuotes = (from requests in serviceModel.ShippingRequest.Select(x => x.ShippingPackages.Select(y => new { address = x.Address, package = y})).SelectMany(z => z)
join quote in serviceModel.QuotesResult.Quotes
on requests.package.Package equals quote.Id
select new { quote = quote, package = requests }).ToList();
var results = addrQuotes.GroupBy(m => m.package.address)
.Select(n => new {
quotes = n.Select(c => c).Select(c1 => new {
address = c1.package.address,
quote = c1.quote
}).ToList()
}).ToList();
}
}
public class ServiceModel
{
public List<ShippingRequest> ShippingRequest { get; set; }
public QuotesResult QuotesResult { get; set; }
}
public class ShippingRequest
{
public string Address { get; set; } // AddressId
public List<ShippingPackage> ShippingPackages { get; set; }
}
public class ShippingPackage
{
public string Package { get; set; } // PackageId
public List<string> ShippingItems { get; set; } // IsSkipped
}
public class QuotesResult
{
public List<Quote> Quotes { get; set; } // PackageId, Cost
}
public class Quote
{
public string Id { get; set; }
public decimal Cost { get; set; }
}
}

Get Collections from object using reflection and getCount (.net 4)

I have a requirement to reflect on a object get all properties that are collections and
1)GetCount for each collection
2)GetTotalCount (allCollectionCount)
3)Call a method with this collection.
Below is what I have done so far with a made up noddy structure for semplicity.
I am stuck in how to call this method and how to get count for collection.
Any suggestions?
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Text;
namespace ConsoleApplication2
{
class Program
{
static void Main()
{
var request = GetDataRequest();
//Get all properties
List<PropertyInfo> propInfoList =
new List<PropertyInfo>(request.GetType().GetProperties(BindingFlags.Instance | BindingFlags.Public));
//Get collections only
var myClassCollections=propInfoList.Where(xxx => xxx.PropertyType.GetInterfaces().Any(x => x == typeof (IEnumerable))).ToList();
var totalCountForAllCollections=????
foreach (var col in myClassCollections)
{
//How do I call my Method DoSomething
// DoSomething<?>(col.?????)
}
}
public void DoSomething<T>(List<T> objectCollection)
{
//etc...
}
private static DataRequest GetDataRequest()
{
DataRequest request = new DataRequest();
request.Addresses.Add(new Address
{
Id = 1,
City = "London",
Postcode = "32131",
Street = "London Road"
});
request.Addresses.Add(new Address
{
Id = 2,
City = "NewYork",
Postcode = "3432",
Street = "NewYork Road"
});
request.Customers.Add(new Customer
{
Id = 1,
Name = "Jo",
Surname = "Bloggs",
});
request.Customers.Add(new Customer
{
Id = 1,
Name = "Jon",
Surname = "Bloggs2",
});
request.Customers.Add(new Customer
{
Id = 1,
Name = "Jonny",
Surname = "Bloggs3",
});
return request;
}
}
public class DataRequest
{
public DataRequest()
{
Customers = new List<Customer>();
Orders = new List<Order>();
Addresses = new List<Address>();
}
public List<Customer> Customers { get; set; }
public List<Order> Orders { get; set; }
public List<Address> Addresses { get; set; }
}
public class Customer
{
public int Id { get; set; }
public string Name { get; set; }
public string Surname { get; set; }
}
public class Order
{
public int Id { get; set; }
public string Name { get; set; }
public string OrderNo { get; set; }
}
public class Address
{
public int Id { get; set; }
public string Street { get; set; }
public string City { get; set; }
public string Postcode { get; set; }
}
}

quick and dirty, here you go...
// ..
static class Program
{
static void Main()
{
var request = GetDataRequest();
//Get propertyValues for properties that are enumerable (i.e. lists,arrays etc)
var collectionProperties = request.GetType()
.GetProperties(BindingFlags.Instance | BindingFlags.Public)
.Where(propertInfo => propertInfo.PropertyType.GetInterfaces().Any(x => x == typeof(IEnumerable)))
.Select(p => p.GetValue(request, null))
.Cast<IEnumerable<object>>().ToList();
var totalCountForAllCollections = 0;
// iterate through the list of propertyValues
foreach (var collectionPropertyValue in collectionProperties)
{
totalCountForAllCollections += collectionPropertyValue.Count();
collectionPropertyValue.DoSomething();
}
System.Console.WriteLine("The total count for all collections is : {0}", totalCountForAllCollections);
System.Console.WriteLine("press any key to exit");
System.Console.ReadLine();
}
public static void DoSomething<T>(this IEnumerable<T> objectCollection)
{
//etc...
// N.B. you will have to use typeof(T) to implement logic specific to the type
// If the logic in this method is non-specific to the typeof(T) then Implement logic accordingly
System.Console.WriteLine("The type of the collection is: {0}", objectCollection.GetType());
System.Console.WriteLine("The count of items in this collection is:{0}", objectCollection.Count());
}
// ..
}
// ..

entity framework - two people with the same data

I want to map a two tables in entity framework 6 and need some help! It is for my chat application; I need to map user conversations into the database. Both group and private messages. For this question however, if you help me with the private messaging mapping, I should hopefully work out the group by myself :) anyway....
Each user can talk to any other user. They however share the same data, which is where I am struggling a bit: how to set the keys to the exact same data without duplication. This is what I have so far:
**EDIT - new code *****
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.Entity;
namespace CodeFirstNewDatabaseSample
{
static void Main(string[] args)
{
using(var db = new PrivateMessageContext())
{
Console.Write("Enter message: ");
var message = Console.ReadLine();
var userFrom = "userFrom";
var userTo = "userTo";
var messageDetail = new PrivateMessageDetail(MessageDate = DateTime.Now, FromUser = userFrom, message = message);
var pm = new PrivateMessageHeader { User1 = userFrom, User2 = userTo, TimeStamp = DateTime.Now };
pm.Messages.Add(messageDetail);
db.PrivateMessages.Add(pm);
db.SaveChanges();
// Display all Blogs from the database
foreach(var pmsg in db.PrivateMessages)
{
var query = pmsg;
Console.WriteLine(pmsg.Message);
}
Console.ReadKey();
}
}
}
public class PrivateMessage
{
public int PrivateMessageId { get; set; }
public string Message { get; set; }
public DateTime TimeStamp { get; set; }
// public int User1Id { get; set; }
public virtual string user1 { get; set; }
// public virtual User user1 { get; set; }
public virtual string user2 { get; set; }
//public int User1Id { get; set; }
// public virtual User user2 { get; set; }
}
public class User
{
public int UserId { get; set; }
public string UserName { get; set; }
}
public class PrivateMessageContext : DbContext
{
public DbSet<PrivateMessage> PrivateMessages { get; set; }
}
public class Send
{
/* void Send(userTo, userFrom, message)
{
using (var db = new PrivateMessageContext()) {
var query = from pm in db.PrivateMessages;
foreach(var msg in pm)
{
var user1 = msg.user1;
var user2 = msg.user2;
if ( (user1==userTo && user2==userFrom) || (user1==userFrom && user2==userTo))
{
msg.Message += message;
return;
}
else {
// pair doesn't exist
var PrivateMessage = new PrivateMessage { user1 = userFrom; user2 = userTo; TimeStamp = DateTime.Now; Message = message; };
db.PrivateMessages.Add(PrivateMessage);
db.SaveChanges();
}
}
}*/
}
}
I am now stuck on two things - how to make a callable class which checks if there is previous message history (the Send() ) and how to use the User username instead of strings...
Thank you
*update 3*
static void Main(string[] args)
{
using(var db = new PrivateMessageContext())
{
Console.Write("Enter message: ");
var message = Console.ReadLine();
var userFrom = "userFrom";
var userTo = "userTo";
var messageDetail = new PrivateMessageDetail(MessageDate = DateTime.Now, FromUser = userFrom, message = message);
var pm = new PrivateMessageHeader { User1 = userFrom, User2 = userTo, TimeStamp = DateTime.Now, Message = messageDetail };
db.PrivateMessages.Add(pm);
db.SaveChanges();
// Display all Blogs from the database
foreach(var pmsg in db.PrivateMessages)
{
var query = pmsg;
Console.WriteLine(pmsg.Message);
}
Console.ReadKey();
}
}
}
public class PrivateMessageContext : DbContext
{
public DbSet<PrivateMessageHeader> PrivateMessages { get; set; }
}

What you probably want is some kind of master/detail. What you would do is create a PrivateMessageHeader type, and this would contain the participants in the private message. Then you would have a PrivateMessageDetail type that would contain the actual messages. There would be a 1 to many association between Header and details.
So something like this:
public class PrivateMessageHeader {
public PrivateMessageHeader() { Messages = new List<PrivateMessageDetail>; }
public int PrivateMessageHeaderId {get;set;}
public DateTime ThreadTime {get;set;} // Date of the start of thread
public string User1 {get;set;}
public string User2 {get;set;} // this could be made to a list to allow multiples
public ICollection<PrivateMessageDetail> Messages {get;set;}
}
public class PrivateMessageDetail {
public int PrivateMessageDetailId {get;set;}
public DateTime MessageDate {get;set;}
public string FromUser {get;set;} // Don't need ToUser, it's already in header
public string Message {get;set;}
public PrivateMessageHeader parent {get;set;}
}