Entity Framework code-first not generating database in SQL Server - asp.net-mvc

I am new to EF code first approach, what I am trying to do is just inserting a record but somehow the database fails to generate in my SQL Server when my SubmitResult method is executed. I placed a breakpoint at unitOfWork.Save(); and it went through without catching any errors, I assume that if my connection string is invalid it would have thrown an exception. What could possibly be causing this?
Thanks.
[HttpPost]
public JsonResult SubmitResult(String signedRequest, String facebookName, String email, int score, String title)
{
DateTime now = ConstantHelper.GetCurrentTime();
try
{
FacebookSignedRequestUtility fbSignedRequestUtility = new FacebookSignedRequestUtility();
fbData = fbSignedRequestUtility.Parse(FacebookUtility.AppSecret, signedRequest);
Entry entry = new Entry();
entry.Fbuid = fbData.FBUID;
entry.FacebookName = facebookName;
entry.Email = email;
entry.Score = score;
entry.Title = title;
entry.CreatedDateTime = now;
entry.ModifiedDateTime = now;
unitOfWork.EntryRepository.Insert(entry);
unitOfWork.Save();
}
catch (Exception ex)
{
return Json(new { status = "false" });
}
return Json(new { status = "true" });
}

Ok found out that my unitOfWork class has some issues, it works if instantiate my db and save.
AmexContext amc = new AmexContext() ;
amc.SaveChanges();

Related

ASP.NET Stored Procedure Call insert VarBinary into sql

I have a string that is data bytes base64EncodedString from iOS which is an extremely long string
let imageStr = imageData.base64EncodedString()
I am calling a .NET Method from my ios that will call a stored procedure to insert these bytes into the database.
Here is my .NET Method, I have the data type set to VarBinary
public string PostLandGradingImages(List<Images> landingCells)
{
try
{
using (connection = new SqlConnection(connectionString))
{
connection.Open();
using (SqlCommand command = new SqlCommand("PostLandGradingImages", connection))
{
command.CommandType = CommandType.StoredProcedure;
for (int i = 0; i < landingCells.Count; i++)
{
command.Parameters.Clear();
SqlParameter parameter1 = new SqlParameter("#Job_No", SqlDbType.VarChar);
parameter1.Value = landingCells[i].jobNo;
parameter1.Direction = ParameterDirection.Input;
command.Parameters.Add(parameter1);
SqlParameter parameter2 = new SqlParameter("#Image", SqlDbType.VarBinary);
parameter2.Value = landingCells[i].imageBytes;
parameter2.Direction = ParameterDirection.Input;
command.Parameters.Add(parameter2);
command.ExecuteNonQuery();
}
}
}
}
catch (Exception e)
{
return e.Message.ToString();
}
return "All Good";
}
Here is my Image Class, notice my imageBytes is defined as a byte[]:
public class Images
{
public string jobNo { get; set; }
public byte[] imageBytes { get; set; }
}
The column I am inserting into is defined as varbinary(MAX)
and here is my stored procedure:
ALTER PROCEDURE [dbo].[PostLandGradingImages]
-- Add the parameters for the stored procedure here
#Job_No varchar(MAX) = NULL,
#Image varbinary(MAX) = NULL
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
-- Insert statements for procedure here
INSERT INTO LandGradingImages (Job_No, ImageBytes) VALUES (#Job_No, #Image)
END
My problem is nothing is getting inserted, I am getting this error in my catch:
Object reference not set to an instance of an object.
My question is, what am I doing wrong? Should I not be sending base64EncodedString or am I not setting my class right? or my db column?
I tried this:
byte[] bytes = System.Convert.FromBase64String(landingCells[i].imageBytes);
SqlParameter parameter2 = new SqlParameter("#Image", SqlDbType.VarBinary, 800000);
parameter2.Value = bytes;
parameter2.Direction = ParameterDirection.Input;
command.Parameters.Add(parameter2);
Still does not work :( and I changed imageBytes to string.
I modified your code a little to the method below. It creates a new CommandType.StoredProcedure for every Image. Also the results are returned per image, so you can see which ones failed. In your method, if you have 10 images, and the 9th failed, you would not know that.
public List<Images> PostLandGradingImages(List<Images> landingCells)
{
//create a connection to the database
using (SqlConnection connection = new SqlConnection(Common.connectionString))
{
//loop all the images
for (int i = 0; i < landingCells.Count; i++)
{
//create a fresh sql command for every Image
using (SqlCommand command = new SqlCommand("PostLandGradingImages", connection))
{
command.CommandType = CommandType.StoredProcedure;
//add the parameters
command.Parameters.Add("#Job_No", SqlDbType.VarChar).Value = landingCells[i].jobNo;
command.Parameters.Add("#Image", SqlDbType.VarBinary).Value = landingCells[i].imageBytes;
try
{
//open the connection if closed
if (connection.State == ConnectionState.Closed)
{
connection.Open();
}
//execute the stored procedure
command.ExecuteNonQuery();
//set the save result to the image
landingCells[i].saveResult = true;
}
catch (Exception ex)
{
//handle error per Image
landingCells[i].errorMessage = ex.Message;
}
}
}
}
return landingCells;
}
In order to track the save result per image I've added two properties to the Image class, but this can be done in various other ways as well.
public class Images
{
public string jobNo { get; set; }
public byte[] imageBytes { get; set; }
public bool saveResult { get; set; }
public string errorMessage { get; set; }
}
A simple test was done with the following code. None of them gave a NullReference Error. Even with both properties being null, a database entry was still made.
//create a new list with Images
List<Images> landingCells = new List<Images>();
//add some dummy data
landingCells.Add(new Images() { jobNo = null, imageBytes = null });
landingCells.Add(new Images() { jobNo = "Job 1", imageBytes = null });
landingCells.Add(new Images() { jobNo = null, imageBytes = new byte[10000] });
landingCells.Add(new Images() { jobNo = "Job 2", imageBytes = new byte[10000] });
//send the images to be saved
landingCells = PostLandGradingImages(landingCells);
//loop all the images to check the result
for (int i = 0; i < landingCells.Count; i++)
{
if (landingCells[i].saveResult == false)
{
//display the result for each failed image
Label1.Text += landingCells[i].errorMessage + "<br>";
}
}
If there is still a NullReference error, that means that your List landingCells itself is null, or an Image object within that List is null (in which case it should never have been added to the List in the first place imho). You can change the snippet easily to check for that.
Consider batching the queries in a transaction. Also you should validate the values provided to the method to make sure that you can call the stored procedure correctly.
public int PostLandGradingImages(List<Images> landingCells) {
int count = 0;
using (var connection = new SqlConnection(connectionString)) {
connection.Open();
//Transaction to batch the actions.
using (var transaction = connection.BeginTransaction()) {
foreach (var image in landingCells) {
if (valid(image)) {//validate input properties.
try {
using (SqlCommand command = connection.CreateCommand()) {
command.CommandType = CommandType.StoredProcedure;
command.CommandText = "PostLandGradingImages";
command.Parameters
.Add("#Job_No", SqlDbType.VarChar, image.jobNo.Length)
.Value = image.jobNo;
command.Parameters
.Add("#Image", SqlDbType.VarBinary, image.imageBytes.Length)
.Value = image.imageBytes;
count += command.ExecuteNonQuery();
}
} catch {
//TODO: Log error
}
}
}
if (landingCells.Count == count) {
transaction.Commit();
}
}
}
return count;
}
private bool valid(Images image) {
return image != null && String.IsNullOrWhiteSpace(image.jobNo)
&& image.imageBytes != null && image.imageBytes.Length > 0;
}

How to save data in multiple tables using Entity Framework?

How to save mixed data in multiple tables if is checked checkbox:
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Create([Bind(Include = "rID,AgentID,karta_br,Datum,patnikID,stanicaOD,stanicaDO,cena,povratna")] tbl_rezervacii tbl_rezervacii)
{
if (ModelState.IsValid)
{
if (tbl_rezervacii.povratna != true)
{
db.tbl_rezervacii.Add(tbl_rezervacii);
db.SaveChanges();
}
else
{
tbl_rezervacii rezervacii = new tbl_rezervacii()
{
???????????????????????
};
db.tbl_rezervacii.Add(rezervacii);
db.SaveChanges();
tbl_povratni povratni = new tbl_povratni()
{
???????????????????????
};
db.tbl_povratni.Add(povratni);
db.SaveChanges();
}
This is code in the controller, and I need to mix data from two forms, and save to two tables, I need something like this, and now my problem is just in else section of implementation.
I make application for Bus Ticket system, and i need this if is checked return way checkbox to add: rID (related with first table tbl_rezervacii), date of returning and relation of returning, include same agent id, price, etc. data which is saved in first tbl_rezervacii table.
MODIFIED CONTROLLER CODE:
public ActionResult Create([Bind(Include = "rID,AgentID,karta_br,Datum,patnikID,stanicaOD,stanicaDO,cena,povratna")] tbl_rezervacii tbl_rezervacii )
{
if (ModelState.IsValid)
{
if (tbl_rezervacii.povratna != true)
{
db.tbl_rezervacii.Add(tbl_rezervacii);
db.SaveChanges();
}
else
{
tbl_rezervacii rezervacii = new tbl_rezervacii()
{
AgentID = tbl_rezervacii.AgentID,
karta_br = tbl_rezervacii.karta_br,
Datum = tbl_rezervacii.Datum,
patnikID = tbl_rezervacii.patnikID,
stanicaOD = tbl_rezervacii.stanicaOD,
stanicaDO = tbl_rezervacii.stanicaDO,
cena = tbl_rezervacii.cena,
povratna = tbl_rezervacii.povratna
};
db.tbl_rezervacii.Add(rezervacii);
//db.SaveChanges();
var rows = db.SaveChanges();
tbl_povratni povratna = new tbl_povratni()
{
rezID = rezervacii.rID,
AgentID = rezervacii.AgentID,
karta_br = rezervacii.karta_br,
DatumP = **tbl_povratni.DatumP**,
patnikID = rezervacii.patnikID,
stanicaPOD = **tbl_povratni.stanicaPOD**,
stanicaPDO = **tbl_povratni.stanicaPDO**,
};
db.tbl_povratni.Add(povratna);
db.SaveChanges();
}
ViewBag.AgentID = new SelectList(db.tbl_agenti, "aID", "agent_ime", tbl_rezervacii.AgentID);
ViewBag.patnikID = new SelectList(db.tbl_patnici, "pID", "ime", tbl_rezervacii.patnikID);
ViewBag.stanicaOD = new SelectList(db.tbl_stanici, "sID", "stanica", tbl_rezervacii.stanicaOD);
ViewBag.stanicaDO = new SelectList(db.tbl_stanici, "sID", "stanica", tbl_rezervacii.stanicaDO);
ViewBag.stanicaPOD = new SelectList(db.tbl_stanici, "sID", "stanica", tbl_rezervacii.tbl_povratni.stanicaPOD);
ViewBag.stanicaPDO = new SelectList(db.tbl_stanici, "sID", "stanica", tbl_rezervacii.tbl_povratni.stanicaPDO);
return View(tbl_rezervacii);
}
return RedirectToAction("Index");
}
How to take data from secondary form and save together in second table?
So, if checkbox is checked, you want to save data into two tables and use primary key of first table (rID) in second table? If rID is auto increment, It will be updated by EF with the value assigned by the database.
tbl_rezervacii rezervacii = new tbl_rezervacii()
{
AgentID = tbl_rezervacii.AgendID,
karta_br = tbl_rezervacii.karta_br
// and so on...
};
db.tbl_rezervacii.Add(rezervacii);
var rows = db.SaveChanges(); // optional, rows will be > 0 if saved successfully.
tbl_povratni povratni = new tbl_povratni()
{
// if rID is auto increment
rID = rezervacii.rID,
// and so on...
};
db.tbl_povratni.Add(povratni);
db.SaveChanges();

dbcontext not saving nor catching exeption

I am using a dbContextwhich is described as the following
public class DbContext: System.Data.Entity.DbContext
{
public DbSet<UserAccount> UserAccounts { get; set; }
public DbSet<Sesison> Sessions { get; set; }
}
And in my login action for some reason after checking with the database that the user is correct i am not able to use another entity of the context to save into the database, whats happens is that i won't get the data saved into the database and it will actually stop executing code after the dc.SaveChanges() but i dont get an exeption on my catch, so what my browser is expiriencing is a 500 internal server error.
public ActionResult Login(LoginViewModel model)
{
using (DbContext dc = new DbContext())
{
var v = dc.UserAccounts.SingleOrDefault(a => a.UserName == model.UserName);
if (v != null)
{
if (GetSHA1(model.Password) == v.Password)
{
Guid sessionGuid =Guid.NewGuid();
var session = dc.Sessions.Add(new Sesison() { SessionID = sessionGuid,StartDateTime=DateTime.UtcNow,UserID = v.UserID,ExpireDateTime=DateTime.UtcNow.AddHours(4)});
System.Web.HttpContext.Current.Session["IsLogin"] = true;
System.Web.HttpContext.Current.Session["Session"] = sessionGuid;
try
{
dc.SaveChanges();
}
catch (System.Data.Entity.Validation.DbEntityValidationException dbEx)
{
Exception raise = dbEx;
foreach (var validationErrors in dbEx.EntityValidationErrors)
{
foreach (var validationError in validationErrors.ValidationErrors)
{
string message = string.Format("{0}:{1}",
validationErrors.Entry.Entity.ToString(),
validationError.ErrorMessage);
// raise a new exception nesting
// the current instance as InnerException
raise = new InvalidOperationException(message, raise);
}
}
throw raise;
}
return Json(new
{
Item1 = "true"
});
}
else
{
return Json(new
{
Item1 = "false",
Item2 = "The username or password you entered is incorrect. Please try again."
});
}
}
else
{
return Json(new
{
Item1 ="false",
Item2 = "The username or password you entered is incorrect. Please try again."
});
}
}
return null;
}
The call to SaveChanges is throwing an exception of a type other than DbEntityValidationException
A quick look at the DbContext SaveChanges call shows that it might throw the following types of exceptions. If you don't want to handle each then you probably want to add a generic Exception handling to find the problem.
// Exceptions:
// T:System.Data.Entity.Infrastructure.DbUpdateException:
// An error occurred sending updates to the database.
//
// T:System.Data.Entity.Infrastructure.DbUpdateConcurrencyException:
// A database command did not affect the expected number of rows. This usually indicates
// an optimistic concurrency violation; that is, a row has been changed in the database
// since it was queried.
//
// T:System.Data.Entity.Validation.DbEntityValidationException:
// The save was aborted because validation of entity property values failed.
//
// T:System.NotSupportedException:
// An attempt was made to use unsupported behavior such as executing multiple asynchronous
// commands concurrently on the same context instance.
//
// T:System.ObjectDisposedException:
// The context or connection have been disposed.
//
// T:System.InvalidOperationException:
// Some error occurred attempting to process entities in the context either before
// or after sending commands to the database.

'System.Linq.IQueryable<NewsSite.Models.Domain.Tbl_News>' does not contain a definition

I Create A News Site With MVC5 But I Have Problem .
in Model i Create A Repository Folder And in this i Create Rep_Setting for
Connect to Tbl_Setting in DataBase .
public class Rep_Setting
{
DataBase db = new DataBase();
public Tbl_Setting Tools()
{
try
{
var qGetSetting = (from a in db.Tbl_Setting
select a).FirstOrDefault();
return qGetSetting;
}
catch (Exception)
{
return null;
}
}
}
And i Create a Rep_News for Main Page .
DataBase db = new DataBase();
Rep_Setting RSetting = new Rep_Setting();
public List<Tbl_News> GetNews()
{
try
{
List<Tbl_News> qGetNews = (from a in db.Tbl_News
where a.Type.Equals("News")
select a).OrderByDescending(s => s.ID).Skip(0).Take(RSetting.Tools().CountNewsInPage).ToList();
return qGetNews;
}
catch (Exception ex)
{
return null;
}
}
But This Code Have Error to Me
OrderByDescending(s=>s.ID).Skip(0).Take(RSetting.Tools().CountNewsInPage).ToList();
Error :
Error 18 'System.Linq.IQueryable<NewsSite.Models.Domain.Tbl_News>' does
not contain a definition for 'Take' and the best extension method overload
'System.Linq.Queryable.Take<TSource>(System.Linq.IQueryable<TSource>, int)' has
some invalid arguments
E:\MyProject\NewsSite\NewsSite\Models\Repository\Rep_News.cs 50 52 NewsSite
How i Resolve it ?
Try it this way. The plan of debugging is to split your execution, this also makes for a more reusable method in many cases. And a good idea is to avoid using null and nullables if you can, if you use them "on purpose" the you must have a plan for them.
DataBase db = new DataBase();
Rep_Setting RSetting = new Rep_Setting();
public List<Tbl_News> GetNews()
{
int skip = 0;
Tbl_Setting tools = RSetting.Tools();
if(tools == null){ throw new Exception("Found no rows in the database table Tbl_Setting"); }
int? take = tools.CountNewsInPage;//Nullable
if(!take.HasValue)
{
// Do you want to do something if its null maybe set it to 0 and not null
take = 0;
}
string typeStr = "News";
List<Tbl_News> qGetNews = (from a in db.Tbl_News
where a.Type.Equals(typeStr)
select a).OrderByDescending(s => s.ID).Skip(skip).Take(take.Value);
return qGetNews.ToList();
}
if qGetNews is a empty list you now don't break everything after trying to iterate on it, like your return null would. instead if returning null for a lit return a new List<>() instead, gives you a more resilient result.
So I said reusable method, its more like a single action. So you work it around to this. Now you have something really reusable.
public List<Tbl_News> GetNews(string typeStr, int take, int skip = 0)
{
List<Tbl_News> qGetNews = (from a in db.Tbl_News
where a.Type.Equals(typeStr)
select a).OrderByDescending(s => s.ID).Skip(skip).Take(take);
return qGetNews.ToList();
}
Infact you shjould always try to avoid returning null if you can.
public class Rep_Setting
{
DataBase db = new DataBase();
public Tbl_Setting Tools()
{
var qGetSetting = (from a in db.Tbl_Setting
select a).FirstOrDefault();
if(qGetSetting == null){ throw new Exception("Found no rows in the database table Tbl_Setting"); }
return qGetSetting;
}
}

BreezeSharp - Query with parameters against the local cache

I am trying to execute query with parameters against local cache or server (if nothing is found in cache).
public async Task<List<T>> Get(IDictionary<string, object> parameters, string resourceName = "", FetchSource fetchSource = FetchSource.None)
{
try
{
var query = resourceName == string.Empty ? EntityQuery.From<T>().WithParameters(parameters) : EntityQuery.From<T>(resourceName).WithParameters(parameters);
var queryResult = await this.ExecuteQuery(query, fetchSource);
var result = queryResult.ToList();
return result;
}
catch (Exception e)
{
return new List<T>(); // return empty result instead
}
}
FetchSource is our enum:
public enum FetchSource
{
None = 0,
FromServer = 1,
FromCache = 2,
FromCacheOrServer = 3
}
And here is ExecuteQuery method:
protected async Task<IEnumerable<T>> ExecuteQuery(EntityQuery<T> query, FetchSource fetchSource = FetchSource.None)
{
//...
if (fetchSource == FetchSource.FromCacheOrServer)
{
var result = query.ExecuteLocally(this.EntityManager); // Throws error
if (result != null && result.Any())
{
return result;
}
return await query.Execute(this.EntityManager);
}
//...
}
When I try to execute query locally this exception is thrown:
{"Unable to cast object of type
'WhereEnumerableIterator`1[StanleySteemer.Nimbus.Client.Common.Model.Proxy.RouteOrder]'
to type
'DataServiceOrderedQuery[StanleySteemer.Nimbus.Client.Common.Model.Proxy.RouteOrder]'."}
Although I couldn't find anything in docs specifically regarding to this subject, I have implemented similar functionality in BreezeJS which was working without issue(UPDATE: it doesn't work correctly):
findWithParametersInCacheOrServer = function (parameters, recordsLimit) {
var query = breeze.EntityQuery
.from(resourceName)
.withParameters(parameters);
var r = executeCacheQuery(query);
if (r) {
if (r.length > recordsLimit) {
return Q.resolve(r);
}
}
return executeQuery(query);
};
function executeCacheQuery(query) {
return entityManagerProvider.manager().executeQueryLocally(query);
}
Data architecture in JavaScript is similar to TempHire example.
Is this a known issue? Is there any workaround for it?
Not sure I understand, neither breeze.js nor breeze.sharp can automatically perform a 'local cache query' that involves parameters. This is because the interpretation of the parameters is only really defined on the server and not on the client.
It sounds as though what you have done is define a custom implementation of your specific 'with parameters' query in breeze.js that completely bypasses Breeze's internal implementation. Is this correct?

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