How to access database in asp.net mvc? [closed] - c#

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In the default asp.net application, I want to access the data of other users. In my database table ASPNETUSERS I have columns such as Id, Email, Password, Gender etc. Now I want to be able to search for a particular Id and get that user's entire details like his/her Email, Password, Gender etc. So how do I do that?
Do I use raw SQL? If so how? (someone on SO mentioned this as a bad idea)
Do I use models or something else? if so how?
This is my ASPNETUSERS Table info. And this is my action in a controller. I want to be able to get an user called "stackoverflow#gmail.com" and send all his details(whatever are there in my table) to the view.
private ApplicationDbContext db = new ApplicationDbContext();
public ActionResult Index(string id = "")
{
//db.someCommand or something to let me get stuff about
//stackoverflow#gmail.com. Could it be db.Database.ExecuteSqlCommand ?
return View("Send All details about my stackoverflow user");
}
Edit: This is what I tried before. I tried to use raw sql and convert it to a string(for testing) and write it to a file on desktop. That way I thought I would at least know that the data in my database is getting passed back to me correctly before I pass it to my view.
This was my line of code that I added just before my action returned.
System.IO.File.WriteAllText(#"C:\Users\Admin\Desktop\log.txt", db.Database.ExecuteSqlCommand("select * from dbo.AspNetUsers").ToString());
I did not get any errors doing so, but I expected my data from the image above to be posted into my file called log.txt on desktop. But I opened log.txt file only to find that "-1" was posted in there.

If you want to get the users from your database, use linq with your ApplicationDBContext object
ApplicationDbContext db = new ApplicationDbContext();
//Manipulate the Where clause to get the conditions you want
IEnumerable<ApplicationUser> users = db.Users.Where(x => x.Email == "stack#overflow.com");
This works with the out of the box ASP.NET individual authentication model (which looks like what you have)

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ASP.NET Razor pages data linking [closed]

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So I am currently trying to create a counsellor appointment booking system using ASP.NET Razor pages. I have 2 models so far, Counsellor and Schedule which have been created as follows:
I am now trying to create a schedule for a counsellor, where the counsellor name is selected from a drop down list containing all counsellors in the database. However, when I try to create the schedule I receive an error saying I cannot insert the value NULL into column Description. So I think it is trying to create a new counsellor object when I try to create the Schedule.
Here is my index.cshtml page and my index.cshtml.cs page for the schedule model
This is my create.cshtml and create.cshtml.cs pages also for schedule model:
Lastly I show the database table designers for both counsellors and schedules:
If anyone can assist, i just want to retrieve counsellor name when creating the schedule.For some reason it is like it is trying to create a new counsellor object so it gives me an error saying i cannot enter the value into the description column.
You can find you are using [Requeired] on public string Description{get;set;} in model Counseller,and you are passing Schedule.Counseller.Description to OnPostAsync in Create page.So when you use
_context.Schedule.Add(Schedule),it will also insert the Counseller,and it will get the error cannot insert the value NULL into column Description.
If you want to add the Counseller when adding the Schedule,you need to set default values of Counseller [Required] properties.

How to Update database from UI which has many textboxes and CheckBox in asp.net and SQL Server? [closed]

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I am new to ASP.net. I have a webform where I have 40 text box 18 drop downs and 29 checkbox. I need to load the all data from these controls to SQL server database table using stored procedure. I dont want to pass all the parameters one by one and update the table.
Is there any other short way to do it? Please help
I am not sure I follow your question here?
The simplest way, would be to do a model object. Create a method that accepts the model object that includes all the data from your form. This methods feeds the stored procedure call.
This is the common way to do it. And the fastest. You need to assign the data to data-fields. There is no way around it really. But of course it can be done in many different ways.
So you want a more specific answer, you will have to elaborate what you mean by:
"I dont want to pass all the parameters one by one and update the
table."
I can't come up with a scenario where it would be desireable to pass each parameter one by one into an update statement...
but you will have to mention each field in your SQL stored procedure, that you want to update.
if that is your only question:
UPDATE table-name
SET column-name = value, column-name = value, ...
WHERE condition
If you have used a model in your view and used Razor syntax to render the relevant controls than if you have a form defined, posting back to the controller that accepts the same model as it's parameter will handle the binding of all the properties back to the model.
You then either parse the model or use the properties and send them down to entity framework, or any other ORM that you might be using, and have it handle the update operation.
[HttpPost]
public ActionResult YourPostMethod(YourModelUsedInView model)
{
// process your model here and send it down to the DB.
}

C# / SQL Server : MVVM insert data into multiple tables [closed]

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I work on a small project just to get to understand the mvvm model in C# better.
I work with a Microsoft SQL Server database with three tables: customer, location and address.
Every customer can have one or more locations, and every location has a specific address.
My current thought how to accomplish this:
First insert the customer.
To insert the location, get the highest customer_id and insert the location with the max(customer_id)
Then, to insert the address, get the max(location_id) and insert the address, with the location id
Is there a better way to do this?
I haven't found any tutorial with an example of inserting data into more than one table, especially not using SQL Server.
And my next problem is: what should I bind to my TextBoxes, so that I can insert the content of it?
I thought about having a save button. This button would then execute a method, where I insert the data from the bound TextBoxes. Should I do this with commands, instead of writing a method?
Thanks already!
Sql server has a OUTPUT clause which you can use
something like
INSERT INTO MyTable VALUES({CustomerName})
OUTPUT INSERTED.ID
then you can store the inserted customer's actual ID and do the rest inserts in separate queries.
As for your second question yes you should do it with Command binding to a method in your View model
The most advisable for your situation is to use a transaction.
Example.- https://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqltransaction(v=vs.110).aspx

How to make website readonly that link from certain websites. asp.net [closed]

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I have a website where a user logs in, can see his information and edit it. There is also another website, something like a site only for admins, where if I click a link it redirects me to the first website, logged in as that user but I can only read his information not edit it. I am having trouble finding out how to make website 1 both readable only and read/writeable.
I am doing this in Asp.NET mvc using C#.
One method would be to check for authorization in the Razor view.
Psuedocode:
#if(User.IsAuthorizedForEdit()
{
#*your edit view code*#
}
else
{
#*your readonly view code*#
}
This does make for some bloaty Razor. The other (arguably, better) alternative is to direct them to the appropriate view in your controller based on user.
Handy-wavy psuedocode to give you an idea:
public ActionResult ViewProfile(int profileId)
{
var user = GetCurrentUser();//without looking at your code, I can't infer this piece.
var profile = GetProfile(profileId);
if(IsAuthorizedToEdit(user, profileId)
{
return View("edit", profile);
}
else
{
return View("view", profile);
}
}
In theory, you already have a read-only view and an edit view, so the latter would be more reusable.

How to hyperlink to retrieve data from database in ASP.NET (with C#)? [closed]

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I am developing job portal which displays different jobs stored in a SQL Server database. I am using ASP.NET and HTML.
I have job_title and unique job_id in my database table. I have created a hyperlink for job_title which is retrieved from database. Now I want to display the details of that particular job on a different page by clicking job_title of that job.
I need job_id for that particular job whose details I want to display on next hyper linked page. The reason for not to use job_title instead of job_id is that job_title is not unique, but job_id is.
Please tell me how to accomplish that or if you have another solution?
You include the value in the query string of the URL.
WebForms:
Something like this:
Click here for details
Then in JobDetails.aspx you would get the value in Page_Load like this:
var jobID = Request.QueryString["jobID"];
Note that the value would be a string, so you'd need to parse it to a numeric type in order to properly use it. int.TryParse() can help with that.
MVC:
Something like this:
Click here for details
Then in the Details action you would have a parameter for the id value:
public ActionResult Details(int id)
{
// Code to get job details and return a View
}

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