How to Executing SQL Query in Entity Framework and Linq MVC C#

I will explain to you how we can use different types of SQL Query methods.

Introduction

 In this post, we will see how to execute native SQL queries, using DB Context.

 You can execute SQL queries using the following types of SQL Query methods. 

 1- SQL Query for a specific entity type.

 2- SQL Query for a primitive data type.

 3- SQL commands.

Let’s start.

SQL Query for a specific entity type

We can use SQLQuery() method to write SQL queries which return an entity object.

Example:

==============================================================

//DbContext  

DbPersonnesEntities db = new DbPersonnesEntities();  

var customerList = db.Customers.SqlQuery("Select * From Customers").ToList<Customers>();  

==============================================================

The code, shown above, selects all the data rows from customer's table. I would like to add that columns returned by SQLQuery must match the property of an entity type, otherwise it will throw an exception.

SQL Query for a primitive data type

In this type, the SQL Query() method will return any primitive types created using the SQL Query method.

Example:

========================================================

//DbContext  

DbPersonnesEntities db = new DbPersonnesEntities();  

int customerId = db.Database.SqlQuery<int>("Select customerId From Customers where customerName='MAHDI'").FirstOrDefault<int>(); 

========================================================

SQL commands

We can use ExcecuteSqlCommand() method to ensure the CRUD operation.

Example:

===========================================================

//DbContext  

DbPersonnesEntities db = new DbPersonnesEntities();  

int result = db.Database.ExecuteSqlCommand("delete from Customers where customerId = 100");  

===========================================================

As you can see, code displayed above will delete a customer that has 100 as customerId.

How to replacing escape characters from JSON in mvc c#

If the json object is a string, in .Net the escape "\" characters are added,
 should you want to clean up the json string, JObject.Parse({string}) as demonstrated
in the following code snippet cleans up nicely:

var myJsonAsString = "{\"Name\": \"John\", \"LastName\": \"Doe\", \"Age\": 199 }";

var myCleanJsonObject = JObject.Parse(myJsonAsString);

Should give us a clean Json object with the escape characters removed.

{
"Name": "John",
"LastName": "Doe",
"Age": 199
}

Display Current Time in C# (C Sharp)

var ab= DateTime.Now.ToString("hh:mm:ss tt", System.Globalization.DateTimeFormatInfo.InvariantInfo);
var cd=  DateTime.Now.ToString("hh:mm:ss.fff tt", System.Globalization.DateTimeFormatInfo.InvariantInfo);

6 How to Get the Most Out of the Course : Flutter Tutorial

3 Why Flutter

1 What is Flutter

How to send http POST request from sql server stored procesdure

--This query enables ole automation procedures.  set 0 to disable
exec master.dbo.sp_configure 'Ole Automation Procedures', 1
RECONFIGURE

--OLE utomation disabled the following error is thrown.
--SQL Server blocked access to procedure 'sys.sp_OACreate' of component 'Ole Automation Procedures' because this component is turned off as part of the security configuration for this server.
--A system administrator can enable the use of 'Ole Automation Procedures' by using sp_configure. For more information about enabling 'Ole Automation Procedures', search for 'Ole Automation Procedures' in SQL Server Books Online.

--Running the above query may result to this erro
--The configuration option 'Ole Automation Procedures' does not exist, or it may be an advanced option.
--To fix this error run the query below and the enable OLE automation


exec master.dbo.sp_configure 'show advanced options', 1
RECONFIGURE

--create/alter a stored proceudre  accordingly
create procedure webRequest
as
----------------------------------------------------------------
DECLARE @authHeader NVARCHAR(64);
DECLARE @contentType NVARCHAR(64);
DECLARE @postData NVARCHAR(2000);
DECLARE @responseText NVARCHAR(2000);
DECLARE @responseXML NVARCHAR(2000);
DECLARE @ret INT;
DECLARE @status NVARCHAR(32);
DECLARE @statusText NVARCHAR(32);
DECLARE @token INT;
DECLARE @url NVARCHAR(256);
DECLARE @Authorization NVARCHAR(200);

--set your post params
SET @authHeader = 'BASIC 0123456789ABCDEF0123456789ABCDEF';
SET @contentType = 'application/x-www-form-urlencoded';
SET @postData = 'KeyValue1=value1&KeyValue2=value2'
SET @url = 'set your url end point here'

-- Open the connection.
EXEC @ret = sp_OACreate 'MSXML2.ServerXMLHTTP', @token OUT;
IF @ret <> 0 RAISERROR('Unable to open HTTP connection.', 10, 1);

-- Send the request.
EXEC @ret = sp_OAMethod @token, 'open', NULL, 'POST', @url, 'false';
--set a custom header Authorization is the header key and VALUE is the value in the header
EXEC sp_OAMethod @token, 'SetRequestHeader', NULL, 'Authorization', 'VALUE'

EXEC @ret = sp_OAMethod @token, 'setRequestHeader', NULL, 'Authentication', @authHeader;
EXEC @ret = sp_OAMethod @token, 'setRequestHeader', NULL, 'Content-type', @contentType;
EXEC @ret = sp_OAMethod @token, 'send', NULL, @postData;

-- Handle the response.
EXEC @ret = sp_OAGetProperty @token, 'status', @status OUT;
EXEC @ret = sp_OAGetProperty @token, 'statusText', @statusText OUT;
EXEC @ret = sp_OAGetProperty @token, 'responseText', @responseText OUT;

-- Show the response.
PRINT 'Status: ' + @status + ' (' + @statusText + ')';
PRINT 'Response text: ' + @responseText;

-- Close the connection.
EXEC @ret = sp_OADestroy @token;
IF @ret <> 0 RAISERROR('Unable to close HTTP connection.', 10, 1);
go