Develop Reference

Same function for updating and Saving?

My code to use the function for updating is here and it works also
[HttpPost]
public bool SaveDefCompny(DefCompanyDTO DefCmpny)
{
using (RPDBEntities db = new RPDBEntities())
{
using (TransactionScope trans = new TransactionScope())
{
//the problem is here incase of saving
var UpdateDefCmpnyId = (from CmpnyId in db.DefCompanies
where CmpnyId.Id == DefCmpny.Id
select CmpnyId).First();
List<DefCompany> list = new List<DefCompany>();
list.Add(UpdateDefCmpnyId);
try
{
foreach (DefCompany DefCmpny1 in list)
{
DefCmpny1.Id = DefCmpny1.Id;
DefCmpny1.ShortName = DefCmpny.ShortName;
DefCmpny1.FullName = DefCmpny.FullName;
DefCmpny1.ContactPerson = DefCmpny.ContactPerson;
DefCmpny1.Address1 = DefCmpny.Address1;
DefCmpny1.CompanyCity = DefCmpny.CompanyCity;
DefCmpny1.CompanyState = DefCmpny.CompanyState;
DefCmpny1.CompanyCountry = DefCmpny.CompanyCountry;
DefCmpny1.ZipPostCode = DefCmpny.ZipPostCode;
DefCmpny1.TelArea = DefCmpny.TelArea;
DefCmpny1.CurrentCurrencyCode = DefCmpny.CurrentCurrencyCode;
db.SaveChanges();
trans.Complete();
}
}
catch (Exception ex)
{
}
}
return false;
}
}
when I try to save instead of updating the line of code
var UpdateDefCmpnyId = (from CmpnyId in db.DefCompanies
where CmpnyId.Id == DefCmpny.Id
select CmpnyId).First();
gives null value and hence saving fails because record is new and not present in database so how to handle null in case of saving how to use try catch so that when value is null it proceed to saving code that add

How about something along these lines:
var UpdateDefCmpnyId = (from CmpnyId in db.DefCompanies
where CmpnyId.Id == DefCmpny.Id
select CmpnyId).FirstOrDefault();
if(UpdateDefCmpnyId == null)
{
//insert
//(handle the id however you need to for insert. depending on your setup, you might be able to leave it empty and let the database put it in for you)
}
else
{
//update
//set the id as you do in the question
}

Updating multiple records that share a many to many relationship fails

Details
I have 2 tables (Procedures, Surgeons) with a lookup table (ProcSurg) to create a many to many relationship.
scar_Requests scar_Procedures scar_ProcSurg scar_Surgeons
------------- --------------- ------------- -------------
RequestID <> ProcedureID <> ProcedureID(fk) <> SurgeonID
... RequestID SurgeonID(fk) ...
...
A single request can have multiple procedures and each procedure can have multiple surgeons.
Everything saves correctly until I have 2 procedures each that share the same Surgeon.
Error: InvalidOperationException was unhandled
The relationship between the two objects cannot be defined because they are attached to different ObjectContext objects.
I separated out the code for saving this part of the record to try to isolate my problem..
Addprocedures is a class that contains 1 Procedure and a list of Surgeons
class Procedure
{
public scar_Procedures Procedure { get; set; }
public List<scar_Surgeons> Surgeons { get; set; }
public void RemoveSurgeon(int SurgeonID)
{
Surgeons.Remove(Surgeons.Where(x => x.SurgeonID == SurgeonID).FirstOrDefault());
}
public Procedure()
{
Surgeons = new List<scar_Surgeons>();
}
}
Saving code: using DBContext
private void SaveProcSurg()
{
using (MCASURGContext db2 = new MCASURGContext())
{
foreach (Procedure p in AddProcedures)
{
if (p.Procedure.RequestID == 0)
{
p.Procedure.RequestID = ReqID;
}
p.Procedure.scar_Surgeons.Clear();
foreach (scar_Surgeons s in p.Surgeons)
{
if (db2.ChangeTracker.Entries<scar_Surgeons>().Where(x => x.Entity.SurgeonID == s.SurgeonID).FirstOrDefault() == null)
{
db2.scar_Surgeons.Attach(s);
}
p.Procedure.scar_Surgeons.Add(s);
}
if (p.Procedure.ProcedureID == 0)
{
db2.scar_Procedures.Add(p.Procedure);
db2.Entry(p.Procedure).State = System.Data.Entity.EntityState.Added;
}
else
{
db2.scar_Procedures.Attach(p.Procedure);
db2.Entry(p.Procedure).State = System.Data.Entity.EntityState.Modified;
}
}
db2.SaveChanges();
}
}
I've tried several different ways of saving the record and this is the closest I've come to doing it correctly.
I feel like it has something to do with the way I'm attaching the surgeons to the entity and then to the procedure. Any help, idea's or suggestions on where I can find an answer would be great!
I've been searching google endlessly for over a week and I've been trying to wrap my mind around what exactly Entity Framework is doing but I'm still pretty new to this.
Edited 9/24/2013
Sorry this is the complete code snippet from the comments section with the req variable included
//Internal variable
private scar_Requests req;
private List<Procedure> AddProcedures = new List<Procedure>();
//Gets a scar_Request from the DB
private void GetRequest()
{
using (MCASURGContext db = new MCASURGContext())
{
req = db.scar_Requests.Include("scar_Procedures.scar_Surgeons").Include("scar_Status").Include("scar_Users.scar_Service").Where(x => x.RequestID == ReqID).FirstOrDefault();
foreach (scar_Procedures p in req.scar_Procedures) { AddProcedures.Add(new Procedure() { Proc = p, Surgeons = p.scar_Surgeons.ToList() }); }
}
}

Keeping with good form I'll post my answer since I think I figured it out. Maybe it will help someone in the future.
I completely re-wrote the saving and cut out a lot of useless code that I was using before and less calls to the DB. There was other methods that I didn't post above that saved other parts of the record that I condensed into a single method.
Basically I get the record and its joined tables from the DB and iterate through all the fields/joined tables that need to be updated and save it back to the DB. (Seems super obvious now but I tried this way before and I must have had something wrong because it didn't work the first few times I tried it this way.)
I don't know if its 100% correct or written up to normal coding standards and I still have some final tweaking to do before its completely done.
private void SaveProcSurg()
{
using (MCASURGContext db2 = new MCASURGContext())
{
//Get Record from DB
scar_Requests sReq = db2.scar_Requests.Include("scar_Users").Include("scar_Status").Include("scar_Procedures.scar_Surgeons").Where(x => x.RequestID == ReqID).FirstOrDefault();
//Update Record fields
sReq.CreationDate = req.CreationDate == null ? DateTime.Now : req.CreationDate = req.CreationDate;
sReq.DateOfSurgery = dtpDateOfSurgery.Value;
sReq.IsDeleted = false;
sReq.IsScheduled = false;
sReq.LatexAllergy = cbLatexAllergy.Checked;
sReq.ModifiedDate = DateTime.Now;
sReq.MRN = txtMRN.Text;
sReq.PatientName = txtPatientName.Text;
foreach (RadioButton rb in gbPatientType.Controls) if (rb.Checked == true) sReq.PatientType = rb.Text;
sReq.PreOpDiagnosis = txtPreOpDiag.Text;
sReq.PrimarySurgeon = txtPrimarySurgeon.Text;
sReq.PrivateComment = txtPrivateComment.Text;
sReq.PublicComment = txtPublicComment.Text;
sReq.RequestID = ReqID;
sReq.StatusID = req.StatusID;
sReq.UserID = req.UserID;
//Update Users/Status
sReq.scar_Users = db2.scar_Users.Where(x => x.UserID == sReq.UserID).FirstOrDefault();
sReq.scar_Status = db2.scar_Status.Where(x => x.StatusID == req.StatusID).FirstOrDefault();
//Attach to DBContext
db2.scar_Requests.Attach(sReq);
//Update Procedures
foreach (Procedure p in AddProcedures)
{
scar_Procedures pro = sReq.scar_Procedures.Where(x => x.ProcedureID == p.Proc.ProcedureID && p.Proc.ProcedureID != 0).FirstOrDefault();
if (pro != null)
{
pro.EnRecovery = p.Proc.EnRecovery;
pro.IsPrimary = p.Proc.IsPrimary;
pro.Laterality = p.Proc.Laterality;
pro.OrthoFastTrack = p.Proc.OrthoFastTrack;
pro.ProcedureID = p.Proc.ProcedureID;
pro.ProcedureText = p.Proc.ProcedureText;
pro.RequestID = ReqID;
pro.Site = p.Proc.Site;
}
else
{
pro = new scar_Procedures();
pro.EnRecovery = p.Proc.EnRecovery;
pro.IsPrimary = p.Proc.IsPrimary;
pro.Laterality = p.Proc.Laterality;
pro.OrthoFastTrack = p.Proc.OrthoFastTrack;
pro.ProcedureID = p.Proc.ProcedureID;
pro.ProcedureText = p.Proc.ProcedureText;
pro.RequestID = ReqID;
pro.Site = p.Proc.Site; ;
pro.scar_Requests = sReq;
}
//Update Surgeons
pro.scar_Surgeons.Clear();
foreach (scar_Surgeons s in p.Surgeons)
{
pro.scar_Surgeons.Add(db2.scar_Surgeons.Where(x=> x.SurgeonID == s.SurgeonID).FirstOrDefault());
}
}
//Set State and Save
db2.Entry(sReq).State = System.Data.Entity.EntityState.Modified;
db2.SaveChanges();
}
}

How to read MSI properties in c#

I want to read properties of MSI in C# in desktop application.I am using following code:
public static string GetMSIProperty( string msiFile, string msiProperty)
{
string retVal= string.Empty ;
Type classType = Type.GetTypeFromProgID("WindowsInstaller.Installer");
Object installerObj = Activator.CreateInstance(classType);
WindowsInstaller.Installer installer = installerObj as WindowsInstaller.Installer;
Database database = installer.OpenDatabase("C:\\DataP\\sqlncli.msi",0 );
string sql = String.Format("SELECT Value FROM Property WHERE Property=’{0}’", msiProperty);
View view = database.OpenView(sql);
Record record = view.Fetch();
if (record != null)
{
retVal = record.get_StringData(1);
}
else
retVal = "Property Not Found";
return retVal;
}
But I am getting error as System.Runtime.InteropServices.COMException was unhandled.
the sqlncli.msi file is physically placed at c:\DataP location. While debugging I found that database does not contain the data after installer.OpenDatabase() statement.
How can I resolve this issue and get MSI properties in C#?

Windows Installer XML's Deployment Tools Foundation (WiX DTF) is an Open Source project from Microsoft which includes the Microsoft.Deployment.WindowsInstaller MSI interop library. It's far easier and more reliable to use this to do these sorts of queries. It even has a LINQ to MSI provider that allows you to treat MSI tables as entities and write queries against them.
using System;
using System.Linq;
using Microsoft.Deployment.WindowsInstaller;
using Microsoft.Deployment.WindowsInstaller.Linq;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
using(var database = new QDatabase(#"C:\tfs\iswix.msi", DatabaseOpenMode.ReadOnly))
{
var properties = from p in database.Properties
select p;
foreach (var property in properties)
{
Console.WriteLine("{0} = {1}", property.Property, property.Value);
}
}
using (var database = new Database(#"C:\tfs\iswix.msi", DatabaseOpenMode.ReadOnly))
{
using(var view = database.OpenView(database.Tables["Property"].SqlSelectString))
{
view.Execute();
foreach (var rec in view) using (rec)
{
Console.WriteLine("{0} = {1}", rec.GetString("Property"), rec.GetString("Value"));
}
}
}
Console.Read();
}
}
}

I did it in following way:
String inputFile = #"C:\\Rohan\\sqlncli.msi";
// Get the type of the Windows Installer object
Type installerType = Type.GetTypeFromProgID("WindowsInstaller.Installer");
// Create the Windows Installer object
WindowsInstaller.Installer installer = (WindowsInstaller.Installer)Activator.CreateInstance(installerType);
// Open the MSI database in the input file
Database database = installer.OpenDatabase(inputFile, 0);
// Open a view on the Property table for the version property
View view = database.OpenView("SELECT * FROM _Tables");
// Execute the view query
view.Execute(null);
// Get the record from the view
Record record = view.Fetch();
while (record != null)
{
Console.WriteLine(record.get_StringData(0) + '=' + record.get_StringData(1) + '=' + record.get_StringData(2) + '=' + record.get_StringData(3));
record = view.Fetch();
}
And its working for me.

The SQL string is incorrect. It should be:
SELECT `Value` FROM `Property` WHERE `Property`.`Property` = ’{0}’

I was trying to re-use this code, and the only change I had to make to get the code posted by Devashri to work is this line:
string sql = String.Format("SELECT `Value` FROM `Property` WHERE `Property`='{0}'", msiProperty);
Watch out for the single quotes!

as of 04/2020 it would be
Type installerType { get; set; }
WindowsInstaller.Installer installerObj { get; set; }
...
installerType = Type.GetTypeFromProgID("WindowsInstaller.Installer");
installerObj = (WindowsInstaller.Installer)Activator.CreateInstance(installerType);
var installer = installerObj as WindowsInstaller.Installer;
...
private void lnkSelectMsi_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
{
WindowsInstaller.Database msiDatabase = installerObj.OpenDatabase(txtMsiPath.Text, 0);
readMsiTableColumn(msiDatabase, cmbTable.Text, cmbColumn.Text);
}
private void readMsiTableColumn(WindowsInstaller.Database msiDatabase, string table)
{
WindowsInstaller.View msiView = null;
Record record = null;
string s = string.Empty;
try
{
msiView = msiDatabase.OpenView($"Select * from _Columns");
msiView.Execute();
record = msiView.Fetch();
int k = 0;
while (record != null)
{
if (record.StringData[1].Equals(table, StringComparison.OrdinalIgnoreCase))
{
k++;
s += $"{record.StringData[3],-50} ";
}
record = msiView.Fetch();
}
s += nl;
s += "".PadRight(50 * k, '-') + nl;
msiView.Close();
msiView = msiDatabase.OpenView($"Select * from {table}");
msiView.Execute();
record = msiView.Fetch();
while (record != null)
{
string recordValue = string.Empty;
for (int i = 1; i < record.FieldCount + 1; i++)
{
try { recordValue += $"{record.StringData[i],-50} "; }
catch (Exception ex) { recordValue += $"{i}. err {ex.Message}; "; }
}
s += recordValue + nl;
record = msiView.Fetch();
}
msiView.Close();
txtRes.Text = s;
}
catch (Exception ex) { txtRes.Text = ex.Message; }
}

Inserting data in a table with a auto increment key C# .NET Linq to SQL

I want to input data into my table (sql 2008) using linq to sql:
public static bool saveEmail(Emailadressen email)
{
TBL_Emailadressen saveMail = new TBL_Emailadressen();
destil_loterijDataContext db = new destil_loterijDataContext();
saveMail.naam = email.naam;
saveMail.emailadres = email.emailadres;
saveMail.lotnummer = email.lotnummer;
try
{
saveMail.naam = email.naam;
saveMail.lotnummer = email.lotnummer;
saveMail.emailadres = email.emailadres;
db.TBL_Emailadressens.InsertOnSubmit(saveMail);
return true;
}
catch (Exception ex)
{
Console.WriteLine("Opslaan niet gelukt!" + ex.ToString());
return false;
}
}
For some reason nothing is being added to this table.
My table has the following fields:
ID (Auto incr int)
Naam (varchar50)
lotnummer (varchar50)
emailadres (varchar50)
My object im trying to save (saveMail) always has an ID = 0 , and i don't know why. I think that is preventing me from saving to the DB?

Be sure to call SubmitChanges on your DataContext-derived class:
using(var dc = new MyDataContext())
{
saveEmail(new Emailadressen(...));
dc.SubmitChanges();
}

Dataset questions

I have two dataset questions.
If I change any cell in a dataset, how I can update this change in a database without using an SQL update query?
How can I see dataset contents in debug mode (to see the data)?

You can't update a database without an UPDATE query. That's how updates happen. You can use libraries that abstract this away so that you don't have to see the query in your code, but the query still has to happen.
You can see the contents of a dataset in debug mode by adding it to your watch list and clicking the little magnifying glass icon. It opens up a window that lets you look at the tables in the dataset.

You can use LINQ to update data into the database, without using T-SQL Update query.

What you're looking for is a DataAdapter. It will manage updating, deleting and inserting changes.

Check this code and adapt to your needs
///<summary>Update Batch records in DataTable</summary>
///<remarks></remarks>
public void UpdateTables(System.Data.DataTable DataTable)
{
if (DataTable.TableName.Length == 0)
{
throw new Exception("The DataTable tablename is nedded.");
}
if (this.State == ConnectionState.Closed)
{
this.Connect();
}
try
{
string strTablename = DataTable.TableName, strSQL;
System.Data.IDbDataAdapter dt = null;
if (DataTable.TableName.Length == 0)
{
throw new Exception("Tablename can't be null.");
}
strSQL = "SELECT * FROM " + strTablename;
if (m_DatabaseType == DatabaseTypeEnum.Access)
{
dt = new System.Data.OleDb.OleDbDataAdapter(strSQL, m_ConnectionString);
System.Data.OleDb.OleDbCommandBuilder cb_a
= new System.Data.OleDb.OleDbCommandBuilder((System.Data.OleDb.OleDbDataAdapter)dt);
dt.InsertCommand = cb_a.GetInsertCommand();
dt.UpdateCommand = cb_a.GetUpdateCommand();
dt.DeleteCommand = cb_a.GetDeleteCommand();
((System.Data.OleDb.OleDbDataAdapter)dt).Update(DataTable);
}
else if (m_DatabaseType == DatabaseTypeEnum.SQLServer)
{
dt = new System.Data.SqlClient.SqlDataAdapter(strSQL, m_ConnectionString);
System.Data.SqlClient.SqlCommandBuilder cb_s
= new System.Data.SqlClient.SqlCommandBuilder((System.Data.SqlClient.SqlDataAdapter)dt);
dt.InsertCommand = cb_s.GetInsertCommand();
dt.UpdateCommand = cb_s.GetUpdateCommand();
dt.DeleteCommand = cb_s.GetDeleteCommand();
((System.Data.SqlClient.SqlDataAdapter)dt).Update(DataTable);
}
else if (m_DatabaseType == DatabaseTypeEnum.Oracle)
{
dt = new System.Data.OracleClient.OracleDataAdapter(strSQL, m_ConnectionString);
System.Data.OracleClient.OracleCommandBuilder cb_o
= new System.Data.OracleClient.OracleCommandBuilder((System.Data.OracleClient.OracleDataAdapter)dt);
dt.InsertCommand = cb_o.GetInsertCommand();
dt.UpdateCommand = cb_o.GetUpdateCommand();
dt.DeleteCommand = cb_o.GetDeleteCommand();
((System.Data.OracleClient.OracleDataAdapter)dt).Update(DataTable);
}
else if (m_DatabaseType == DatabaseTypeEnum.Odbc)
{
dt = new System.Data.Odbc.OdbcDataAdapter(strSQL, m_ConnectionString);
System.Data.Odbc.OdbcCommandBuilder cb_c
= new System.Data.Odbc.OdbcCommandBuilder((System.Data.Odbc.OdbcDataAdapter)dt);
dt.InsertCommand = cb_c.GetInsertCommand();
dt.UpdateCommand = cb_c.GetUpdateCommand();
dt.DeleteCommand = cb_c.GetDeleteCommand();
((System.Data.Odbc.OdbcDataAdapter)dt).Update(DataTable);
}
else
{
throw new NotImplementedException();
}
DataTable.AcceptChanges();
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}