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ASP.Net Calling method from another namespace

I have two projects, the first one with a ClassLibraryServer namespace and Output method as following :
namespace ClassLibraryServer
{
public class Output
{
public static void Card(tblCard card, int myProperty)
{
if (kort.fltNr.Length != 6)
return;
using (myDataContext db = new myDataContext(ClassLibrary.Settings.Instance.SqlS))
{
tblReader[] readers = (from row in db.tblReader
where !row.fltOffline
select row).ToArray();
bool blocked = (db.tblCardBlocked.Where(b => b.fltProperty == myProperty && b.fltCard == card.id).FirstOrDefault() != null);
foreach (tblReader reader in readers)
{
Card(card, reader, blocked);
}
}
}
}
}
The Card method in foreach loop calls another method (Overloading the first card method) which has three parameters and inserts data to a sql table, I won't share it here as it takes too much space.
Now I want to call above method in another project with namespace ExtControlModule:
namespace ExtControlModule
{
public class TimeModule
{
using (ModuleDataContext dbsys = new ModuleDataContext(ClassLibrary.Settings.Instance.SqlS)) {
var loungee = (from tblLounge in dbsys.tblLounges
select tblLounge).ToList();
var lasaresFas = 0;
foreach (var LoungeRow in loungee)
{
lasaresFas= Convert.ToInt32(dbsys.tblLasares.FirstOrDefault(f => f.id == LoungeRow.fltCardreader).fltproperty);
tblCard cardLoading = dbsys.tblCard.FirstOrDefault(t => t.id == res.fltCardnumber);
Output.Card(cardLoading, lasaresFas);
}
}
}
Now when I want to assign parameters to Output.Card in ExtControlModule I get the following error in cardLoading parameter in Output.Card:
Argument !: cannot convert from 'ExtControlModule.tblCard' to ClassLibrary.db.tblCard'
ClassLibrary is another project in the same Solution which contains a public class Settings with the SqlS property which facilitate connection to SQL database.
Struggling with this for many days as I am new to both ASP.NET and Sql, hope my question is clear enough.

call method
ClassLibraryServer.Output.Card(cardLoading, lasaresFas);

Compiler says dynamic property is missing but I can see it

I'm starting to dive into the world of C# Dynamics and Metaprogramming, and having some trouble.
I managed to create a CodeDom tree, and generate the following code:
namespace Mimsy {
using System;
using System.Text;
using System.Collections;
internal class JubJub {
private int _wabeCount;
private ArrayList _updates;
public JubJub(int wabeCount) {
this._updates = new ArrayList();
this.WabeCount = wabeCount;
}
public int WabeCount {
get {
return this._wabeCount;
}
set {
if((value < 0))
this._wabeCount = 0;
else
this._wabeCount = value;
this._updates.Add(this._wabeCount);
}
}
public string GetWabeCountHistory() {
StringBuilder result = new StringBuilder();
int ndx;
for(ndx = 0; (ndx < this._updates.Count); ndx = ndx + 1) {
if((ndx == 0))
result.AppendFormat("{0}", this._updates[ndx]);
else
result.AppendFormat(", {0}", this._updates[ndx]);
}
}
}
}
I am then compiling dynamically this namespace to an assembly named "dummy".
I can succesfully get an instance of this Type:
string typeName = "Mimsy.JubJub";
Type type = dummyAssembly.GetType(typeName);
dynamic obj = Activator.CreateInstance(type, new object[] { 8 });
//obj is a valid instance type
If I debug this code, I can see in the debugger that obj actually has the property WabeCount:
However, when trying to access this property, the compiler shouts that the dynamic property does not exist.

There are one or perhaps two problems with your code:
You are using an internal class, and trying to access it with dynamic. The two things don't play well together. See https://stackoverflow.com/a/18806787/613130. Use public clasas
You need to cast the value before assigning it to wabeCount, like:
obj.WabeCount = (int)wabes[ndx]
Note that technically, if your "main" assembly is strong named, you could add the InternalsVisibleToAttribute to the "dynamic" assembly to make its internal "things" visible to the main assembly... I do think it would be wasted work.

Encapsulation with multiple classes C#

So my question is over basic encapsulation. I know I am setting up my getters and setters right (I actually have a question later about this) but I have multiple classes. I have another class and I understand that I am making pieces of my code view-able to my outside class by making certain things public. So I think I set up my first code file right. (Some background, I have a class that is connecting to a database and then another that is encapsulating all the data. The first code section posted is the encapsulating part, I then post my three methods I was messing up on.)
I feel okay with the getting and setting, I feel a little unsure of my constructor. I feel like I put my variables in the parameter list so that I put values in them from my outside class? Right? or should I be putting public forms of my private variables in my other code file and then passing those into my constructor in that same file?
/ this my first code file
using System;
public class clsEncapsulate
{
private int mID;
private string mName;
private string mClassification;
private DateTime mConvocationDate;
private string mLocation;
public int ID
{
get
{
return mID;
}
set
{
mID = value;
}
}
public string Name
{
get
{
return mName;
}
set
{
mName = value;
}
}
public string Classification
{
get
{
return mName;
}
set
{
mName = value;
}
}
private DateTime ConvocationDate
{
get
{
return mConvocationDate;
}
set
{
mConvocationDate = value;
}
}
private string Location
{
get
{
return mLocation;
}
set
{
mLocation = value;
}
}
public clsEncapsulate(int id, string name, string classification, DateTime convocationDate, string location)
{
bool running = false;
while(running == false)
{
ID = mID;
Name = mName;
Classification = mClassification;
ConvocationDate = mConvocationDate;
Location = mLocation;
running = true;
}
}
}
In my second code file I am just going to put the methods that I am having trouble with.
private void refreshbox()
{
string formattedConvocation;
string formattedDateTime;
string formattedConvocationName;
lstConvocations.Items.Clear();
foreach (clsEncapsulate currentConvocation in mConvocationAL)
{
formattedConvocationName = currentConvocation.Name;
formattedConvocationName = truncateString(formattedConvocationName, 30);
formattedConvocation = formattedConvocationName.PadRight(33);
formattedConvocation += currentConvocation.Classification.PadRight(17);
formattedDateTime = currentConvocation.ConvocationDate.ToShortDateString().PadRight(10)
+ currentConvocation.ConvocationDate.ToShortTimeString().PadLeft(8);
formattedConvocation += formattedDateTime;
lstConvocations.Items.Add(formattedConvocation);
}
}
Alright, so in order for my second code file to manipulate the variables in the first code file, I need to expose them to this method. I didn't know if I should be putting my public variables in the constructor, or if I should be declaring them somewhere in my first code file. I was very unsure of how to expose these variables to this method. I've fiddle around with it but my book doesn't address this situation exactly and I was having trouble figuring it out.
If someone does answer this question please break down why you're going to put what you're going to put! I want to understand why, say, I put my public variables in one place, and not another. Or why I declare an object of my encapsulate class in one place and not another. I was trying to declare an encapsulate object in my method so it would give this method access to the variables, but it wasn't working! Please tell me what I was doing wrong or if you want me to post more of my code.
Below are the two other methods I was messing up on.
/ second method from my second code file I was messing up on:
private void displayProperties(int index)
{
if (index == -1)
{
return;
}
clsEncapsulate selectedValue = (clsEncapsulate)mConvocationAL[index];
txtConvocationName.Text = selectedValue.Name;
txtConvocationClassification.Text = selectedValue.Classification;
txtConvocationDate.Text = selectedValue.ConvocationDate.ToShortDateString();
txtConvocationTime.Text = selectedValue.ConvocationDate.ToShortTimeString();
txtConvocationLocation.Text = selectedValue.Location;
txtID.Text = selectedValue.ID.ToString();
}
/ last method I was messing up on:
private void readConvocations(string filterConstraint, string sortField, string sortOrder)
{
OleDbConnection connection = null;
OleDbDataReader reader = null;
try
{
connection = new OleDbConnection();
connection.ConnectionString = mConnectionString;
connection.Open();
string statement = "SELECT ID, Name, Classification, Location, Date FROM Convocations ";
if(filterConstraint != "")
{
statement += "WHERE Name LIKE " + toSQL(filterConstraint, true) + " ";
}
string statement2 = statement;
statement = string.Concat(new string[]
{
statement2, "ORDER BY ", sortField, " ", sortOrder
});
OleDbCommand oleDbCommand = new OleDbCommand(statement, connection);
reader = oleDbCommand.ExecuteReader();
mConvocationAL.Clear();
while(reader.Read())
{
clsEncapsulteconvocation = new clsEncapsulate();
convocation.ID = (int)reader["ID"];
convocation.Name = (string)reader["Name"];
convocation.Classification = (string)reader["Classification"];
convocation.Location = (string)reader["Location"];
convocation.ConvocationDate = (DateTime)reader["Date"];
mConvocationAL.Add(convocation);
}
}
finally
{
if (reader != null)
{
reader.Close();
}
if (connection != null)
{
connection.Close();
}
}
}
Tell me if you need me to elaborate more to help you understand my situation. I am new at learning vocabulary and want to understand this! Thank you for helping. :)

The code you provided is one public object and a bunch of private methods so its difficult to get the overall picture of how your code it working together but there are a few principles you can apply to make your code better structured, now and in the future.
Have a read about SOLID (http://en.wikipedia.org/wiki/SOLID_(object-oriented_design)). The S and the D would apply well to your example.
Also you mentioned construtors and private properties. Try looking into Imutable types. That means once the object is created you cannot change it. For your clsEncapsulate class that would mean making your fields read only and remove the public setters.
Good luck.

Using SqlDependency results in constant updates

I pulled an example from this MSDN page and have used it pretty much verbatim. When run the code compiles properly but changeCount increments endlessly whether or not there has actually been a change to the data returned. When a change actually has occurred dataGridView1 reflects the change correctly. Why does my SqlDependency seem like it's firing in a loop even though there apparently have been no changes?
Here's the source:
#region Using directives
using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Runtime.InteropServices;
using System.Security.Permissions;
using System.Text;
using System.Windows.Forms;
#endregion
namespace PreAllocation_Check
{
public partial class Form1 : Form
{
int changeCount = 0;
const string tableName = "MoxyPosition";
const string statusMessage = "Last: {0} - {1} changes.";
DataSet dataToWatch = null;
SqlConnection MoxyConn = null;
SqlCommand SQLComm = null;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
if (CanRequestNotifications())
{
SqlDependency.Start(GetConnectionString());
if (MoxyConn == null)
MoxyConn = new SqlConnection(GetConnectionString());
if (SQLComm == null)
{
SQLComm = new SqlCommand(GetSQL(), MoxyConn);
SqlParameter prm = new SqlParameter("#Quantity", SqlDbType.Int);
prm.Direction = ParameterDirection.Input;
prm.DbType = DbType.Int32;
prm.Value = 100;
SQLComm.Parameters.Add(prm);
}
if (dataToWatch == null)
dataToWatch = new DataSet();
GetData();
}
}
private void Form1_FormClosed(object sender, FormClosedEventArgs e)
{
SqlDependency.Stop(GetConnectionString());
if (MoxyConn != null)
MoxyConn.Close();
}
private bool CanRequestNotifications()
{
try
{
SqlClientPermission SQLPerm = new SqlClientPermission(PermissionState.Unrestricted);
SQLPerm.Demand();
return true;
}
catch
{
return false;
}
}
private string GetConnectionString()
{
return "server=***;database=***;user id=***;password=***";
}
private void GetData()
{
dataToWatch.Clear();
SQLComm.Notification = null;
SqlDependency SQLDep = new SqlDependency(SQLComm);
SQLDep.OnChange += new OnChangeEventHandler(SQLDep_OnChange);
using (SqlDataAdapter adapter = new SqlDataAdapter(SQLComm))
{
adapter.Fill(dataToWatch, tableName);
dataGridView1.DataSource = dataToWatch;
dataGridView1.DataMember = tableName;
}
}
private string GetSQL()
{
return "SELECT PortID, CONVERT(money, SUM(PreAllocPos), 1) AS PreAllocation, CONVERT(money, SUM(AllocPos), 1) AS Allocation, CONVERT(money, SUM(PreAllocPos) - SUM(AllocPos), 1) AS PreLessAlloc " +
"FROM MoxyPosition " +
"WHERE CONVERT(money, PreAllocPos, 1) <> CONVERT(money, AllocPos, 1) " +
"GROUP BY PortID " +
"ORDER BY PortID ASC;";
}
void SQLDep_OnChange(object sender, SqlNotificationEventArgs e)
{
ISynchronizeInvoke i = (ISynchronizeInvoke)this;
if (i.InvokeRequired)
{
OnChangeEventHandler tempDelegate = new OnChangeEventHandler(SQLDep_OnChange);
object[] args = { sender, e };
i.BeginInvoke(tempDelegate, args);
return;
}
SqlDependency SQLDep = (SqlDependency)sender;
SQLDep.OnChange -= SQLDep_OnChange;
changeCount++;
DateTime LastRefresh = System.DateTime.Now;
label1.Text = String.Format(statusMessage, LastRefresh.TimeOfDay, changeCount);
GetData();
}
}
}
Edit: It's worth noting that the database I want to run this against does not currently have the Broker Service enabled, and so to test my code I backed up my target database and restored it with a new name, then ran ALTER DATABASE my_db_name SET ENABLE_BROKER against it. All of my testing has been on this alternate database, which means I'm the only user on it.

This is an old question, but the problem is that your query doesn't meet the requirements.
Short answer:
add schema name to the table "FROM DBO.MoxyPosition " +
Longer answer:
You can see a list of requirements here, which are very similar to those of creating an indexed view. When a SQL Dependency is registered, if it is invalid the notification immediately fires letting you know it's invalid. When you think about it, this makes sense, because how can Visual studio know what the internal requirements are for the SQL Engine?
So in your SQLDep_OnChange function you'll want to look at the reason the dependency fired. The reason is in the e variable (info, source, and type). Details on the event object can be found here:
Info options
Source
Type
For your specific case notice how MS describes the Type property :
Gets a value that indicates whether this notification is generated
because of an actual change, OR BY THE SUBSCRIPTION.

I had a similar problem. Turns out doing SELECT * FROM dbo.MyTable was causing the update to fire constantly. Changing to SELECT Id, Column1, Column2 FROM dbo.MyTable fixed the problem.
It doesn't look like you're using * in your query, but you might try simplifying your query to see if you still have the issue.

I don't have an answer for this, but you did break at least one of the rules here: http://msdn.microsoft.com/en-us/library/aewzkxxh.aspx
when you failed to use two-part table names. Change MoxyPosition to dbo.MoxyPosition and review the rules linked above. I hope it helps, but something tells me something else is at fault here.

see what the Type of the SqlNotificationEventArgs is in your handler (defined as below). If you see it hit hundreds of times and the Type is Subscribe each time then your SQL statement is wrong - see guidelines in other postings
private void HandleOnChange(object sender, SqlNotificationEventArgs e)
{
...
var someType = e.Type; /*If it is Subscribe, not Change, then you may have your SQL statement wrong*/
...
}

LINQ to Entities - Best way to accomplish this?

OK, I am mostly a LAMP developer so I am new to the entity framework. However, I am familiar with the basics in LINQ and have generated a entity model from my DB. Now here is my requirement:
I have a datagrid on a WinForm that will be refreshed from a data source on a remote server every few seconds as changes to the dataset are made from other sources. Obviously, I'd like to construct a lambda expression to get the right anonymous type to satisfy the columns that needs to be shown in my datagrid. I have done this and here is the result (I'm using a custom datagrid control, btw):
And my code thus far:
Models.dataEntities objDB = new Models.dataEntities();
var vans = from v in objDB.vans
select v;
gcVans.DataSource = vans;
OK, so now I have my basic data set. One problem I had is that the "Status" column will show a calculated string based on several parameters in the data set. I added this to my entities via a partial class. As you can see in the screenshot, this is working correctly:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace WindowsFormsApplication1.Models {
public partial class van {
public string van_status {
get {
if (this.is_offline == 1) {
return "Offline";
} else if (this.is_prayer_room == 1) {
return "In Prayer Room";
} else {
return "TODO: Create statuses";
}
}
}
}
}
This added property works fine. However, the second I try to project the status in an anonymous type so I can also retrieve the school name, I get an error:
Models.dataEntities objDB = new Models.dataEntities();
var vans = from v in objDB.vans
select new {
van_name = v.van_name,
school_name = v.school.school_name,
capacity = v.capacity,
phone = v.phone,
van_status = v.van_status
};
gcVans.DataSource = vans;
So, I have two questions:
1) If I cannot use computed properties of my partial classes in LINQ projections, how am I supposed to show my computed string in my datagrid?
2) Am I even approaching this correctly? When I resolve #1, how would I refresh this data (ie during a timer fire event)? Would I simply call objDB.refresh() and then tell my datagrid to update from the datasource? Does calling that method actually run the lambda expression above or does it load everything from the DB?
Thanks for any assistance with this. Also, if you have any best practices to share that would be awesome! I hope I explained this as thoroughly as you need to provide assistance.

1) Instead of modifying your EF object with a partial class you could always create your own class that contains your read only property van_status. The code you've got would be nearly identical:
Models.dataEntities objDB = new Models.dataEntities();
gcVans.DataSource = from v in objDB.vans
select new DisplayVan {
van_name = v.van_name,
school_name = v.school.school_name,
capacity = v.capacity,
phone = v.phone,
};
The van_status property, since it's read-only, will not need to be specified in the query.
2) I'm more a web developer than a desktop developer so I'll give you my take on how to refresh the grid (it may not be the preferred methodology for fat clients)...
I'm reluctant to trust .Refresh() methods and hope all works to maximal efficiency and work properly. Instead, encapsulate the code from #1 in a method of your own and invoke it from your timer event firing (or however you choose to implement the periodic refresh).

Another good option would be to create an extension method.
Here is a simple example:
using System;
namespace WindowsFormsApplication1 {
static class Program {
[STAThread]
static void Main() {
Van van = new Van();
string status = van.GetStatus();
}
}
public static class VanExtension {
public static string GetStatus(this Van van) {
if(van.is_offline == 1) {
return "Offline";
}
else if(van.is_prayer_room == 1) {
return "In Prayer Room";
}
return "TODO: Create statuses";
}
}
public class Van {
public int is_offline { get; set; }
public int is_prayer_room { get; set; }
}
}
Be sure to put this extension class in the same namespace as the entity class.