Module 3: Using Microsoft .NET- Based Languages

Module 3:Using Microsoft .NET- Based Languages

Overview • Overview of the .NET-Based Languages • Comparison of the .NET-Based Languages • Creating a Component Using Visual Studio .NET

Lesson: Overview of the .NET-Based Languages • Multiple Language Support • The Common Language Runtime • The Common Language Runtime Components • Runtime Compilation and Execution • What are Namespaces? • Using Namespaces

Multiple Language Support • The .NET Framework is designed to support many languages • More than 20 languages currently supported • Microsoft provides Visual Basic .NET, C#, Visual J# .NET, and JScript .NET • Benefits of multiple-language support • Code modules are reusable • API access is the same for all languages • The right language is used for the right task • Performance is roughly equal between all languages

The Common Language Runtime • One runtime for all . NET-Based Languages • Manages threads and memory • Garbage collection • Enforces code security • Eliminates DLL versioning problems • Multiple versions of a DLL can run simultaneously • Applications can specify a version of a DLL to use

Type Checker Exception Manager The Common LanguageRuntime Components .NET Framework Class Library Support Thread Support COM Marshaler Security Engine Debug Engine MSIL to Native Compilers Code Manager Garbage Collector Class Loader

Which language? Visual Basic .NETcompiler MSIL C#compiler JITcompiler Runtime Compilation and Execution default.aspx C# code Visual Basic .NET code HTML Runtime Nativecode

What are Namespaces? • Group related classes • Logical, not physical, grouping • Namespaces are hierarchical • Decrease naming conflicts • Imports keyword in Visual Basic .NET code • Using keyword in C# code Imports System.Data.SqlClient using System.Data.SqlClient;

Using Namespaces • Implicit object declaration • Explicit object declaration Imports System.Web.UI.WebControls ... Dim listBox1 As New ListBox() listBox1.Items.Add("First Item") using System.Web.UI.WebControls; ... ListBox listBox1 = new ListBox(); listBox1.Items.Add("First Item"); Dim listBox1 As New System.Web.UI.WebControls.ListBox() listBox1.Items.Add("First Item") System.Web.UI.WebControls.ListBox listBox1 = new System.Web.UI.WebControls.ListBox(); listBox1.Items.Add("First Item");

Lesson: Comparison of the .NET-Based Languages • Visual Basic .NET • C# • Choosing a Language • Practice: Language Translation

Visual Basic .NET • Visual Basic .NET is the latest version of Visual Basic • True object-oriented language • Visual Basic Scripting Edition (and JScript) are still used for client-side script Private Sub Button1_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click Dim i As Integer = 0 Dim x As Double = TextBox1.Text For i = 0 To 4 x *= 2 Label1.Text = Label1.Text & x & "," Next End Sub

C# • C# is a new language • Similar to Java, Visual C++, and Pascal private void Button1_Click(object sender, System.EventArgs e) { int i = 0; double x = Convert.ToDouble(TextBox1.Text); for (i=0; i<=4; i++) { x *= 2; Label1.Text = Label1.Text + x + ","; } }

Choosing a Language • .NET Framework class library is the same regardless of language • Performance • All languages are compiled to MSIL • Only performance difference is how each language compiler compiles to MSIL • The runtime compiles all MSIL the same, regardless of its origin • Development experience • C# is similar to Java, C, Visual C++, and Pascal • Visual Basic .NET is similar to Visual Basic • Browser compatibility • ASP.NET code is server-side code, so browser compatibility is not an issue

Practice: Language Translation • Students are: • Given code in C#, and will then translate it into Visual Basic .NET • Given code in Visual Basic .NET, and will then translate it into C# • Time: 5 minutes

Lesson: Creating a Component Using Visual Studio .NET • What are Classes and Components? • Creating a Class • Using Components in an ASP.NET Web Form • Demonstration: Creating a Class in Visual Studio .NET

component What are Classes and Components? • Classes are groups of code with no user interface • Components are compiled classes • Components are compiled as DLL files • Components are used for sharing code between applications Web application Web application Windows application

Creating a Class • Create a Class Library project in Visual Studio .NET • Visual Studio .NET creates a default namespace • Create methods of the class Public Class Shipping Function ShippingCost _ (ByVal sngPrice As Single) As Single '… Return (sngShipping) End Function End Class public class Shipping { public Single ShippingCost (Single sngPrice) { //… return sngShipping; } }

Using Components in an ASP.NET Web Form • Add a reference to the DLL • Instantiate the class object: • Use the object: CompanyA.Shipping x = new CompanyA.Shipping(); Dim x As New CompanyA.Shipping component.dll component.dll Namespace CompanyA Class Shipping Function ShippingCost (…) End ClassEnd Namespace namespace CompanyA { class Shipping { public void ShippingCost (…) { } } } sngShipping = _ x.ShippingCost(sngPrice) sngShipping = x.ShippingCost(sngPrice);

Demonstration: Creating a Class in Visual Studio .NET • Create a new Class Library project • Create a “Hello World” method • Call it from an ASP.NET page

Review • Overview of the .NET-Based Languages • Comparison of the .NET-Based Languages • Creating a Component Using Visual Studio .NET

Lab 3: Building a Microsoft Visual Studio .NET Component Logon Page Login.aspx Logon Page Login.aspx BenefitsHome PageDefault.aspx BenefitsHome PageDefault.aspx CohoWinery Page HeaderHeader.ascx Page HeaderHeader.ascx ASPState ASPState Menu ComponentClass1.vb Menu ComponentClass1.vb or Class1.cs Registration Register.aspx Registration Register.aspx Web.config Web.config tempdb tempdb Life InsuranceLife.aspx Life InsuranceLife.aspx RetirementRetirement.aspx RetirementRetirement.aspx MedicalMedical.aspx MedicalMedical.aspx DentalDental.aspx DentalDental.aspx XML Web ServicedentalService1.asmx XML Web ServicedentalService1.asmx ProspectusProspectus.aspx ProspectusProspectus.aspx DoctorsDoctors.aspx DoctorsDoctors.aspx User Controlnamedate.ascx User Controlnamedate.ascx Lab Web Application Lab Web Application XML Files XML Files Doctors Doctors Dentists Dentists

Module 3: Using Microsoft .NET- Based Languages