Enable CORS in DotNet core in Startup.cs file

Browser security prevents a web page from making requests to a different domain than the one that served the web page. This restriction is called the same-origin policy. The same-origin policy prevents a malicious site from reading sensitive data from another site. Sometimes, you might want to allow other sites to make cross-origin requests to your app. Example Below  

public void ConfigureAuthentication(IServiceCollection services)

        {

            JwtSecurityTokenHandler.DefaultInboundClaimTypeMap.Clear();

            services.AddCors(options =>

            {

                options.AddPolicy("CorsPolicy",

                    builder => builder

                    .SetIsOriginAllowed((host) => true)

                    .AllowAnyMethod()

                    .AllowAnyHeader()

                    .WithExposedHeaders("Content-Disposition")

                    .AllowCredentials());

            });

                   }

Ref and Out

ref object a, out object out specifies that the parameter is an output parameters, i.e. it has no value until it is explicitly set by the method. ref specifies that the value is a reference that has a value, and whose value you can change inside the method.

DataTable Rows filter

DataView dv = dsDetail.Tables["Employee"].DefaultView; dv.RowFilter = "Id in(10,2,1,5,6,1)"; DataTable dt = dv.ToTable(); ((Repeater)ctrl).DataSource = dt; ((Repeater)ctrl).DataBind();

What Happens When a Request Reaches IIS

This is the link for All the details related parsing asp.net page and generating Requst and Response


http://msdn.microsoft.com/en-us/library/ms972974.aspx

Disable Browser Back Button using Javascript

head runat="server">
script type="text/javascript" language="javascript">
javascript:window.history.forward(0);
/script>
/head>

Disable Browser Back Button using Javascript

head runat="server">
script type="text/javascript" language="javascript">
javascript:window.history.forward(0);
/script>
/head>

Microsoft Enterprises Library

Microsoft Enterprises Library provide API where we dont need to open and close connection and they have sme predefind method .You dont need to create your own method .it has pedefined method for all that things for insert update delete retrieve and some more specific operation...........

You have to download the Entterprise lIbrary first and Add some Dll through AddReferences from a bin folder of Enterprises Library add

using Microsoft.Practices.EnterpriseLibrary.Data.dll
using Microsoft.Practices.EnterpriseLibrary.Common..dll

and Add the classes in code behind

using Microsoft.Practices.EnterpriseLibrary.Data.Sql;
using Microsoft.Practices.EnterpriseLibrary.Data.Configuration;
using Microsoft.Practices.EnterpriseLibrary.Common.Configuration;
using Microsoft.Practices.EnterpriseLibrary.Data;


//Retrieve and Insert value Using Entrprises library

protected void Page_Load(object sender, EventArgs e)
{
Database db = DatabaseFactory.CreateDatabase();
string sqlcommand = "select * from emp";
System.Data.Common.DbCommand dbCommand = db.GetSqlStringCommand(sqlcommand);
using (IDataReader reader = db.ExecuteReader(
dbCommand))
{
Gridview1.DataSource = reader;
Gridview1.DataBind();
}
}
public void save(string name)
{
DatabaseFactory.CreateDatabase().ExecuteNonQuery("inserts12",name);
}
protected void Button1_Click(object sender, EventArgs e)
{
save("subhash");
}

/////////web.config file
inside the ConfigSection
section name="dataConfiguration" type="Microsoft.Practices.EnterpriseLibrary.Data.Configuration.DatabaseSettings,Microsoft.Practices.EnterpriseLibrary.Data" />

after closing configsection You have to add

/configSections>
dataConfiguration defaultDatabase="Master1"/>

//dataconfiguration same name as the connection string because DatabaseFactory.CreateDatabase(); using for connection

//connection string

add name="Master1" providerName="System.Data.SqlClient" connectionString="Data Source=subhash-9f7eec2;user id=;password=;database=Master;integrated security=sspi;"/>