Linglom's blog » VB.NET

Creating Graph with VB.NET, Part 3: Data Binding Chart to Database

linglom — Thu, 27 May 2010 09:40:36 +0000

From Part 1: Basic Chart and Part 2: Customize Chart, you see how to create a basic chart using GUI (no coding). But the chart is static, it’s lack flexibility which means that you cannot change properties or data of the chart while the application is running. Therefore, I will show how to create a chart by coding and bind data from a SQL Server’s database to the Chart control.

On this example, I will create a connection to “Northwind” database on this SQL Server “BKKSQL001\INSTANCE01” and query product name and units in stock from “Products” table. Then, I create a chart and bind the query’s result to the chart.

Step-by-step

Create a new Windows Application project on VB.NET and type name as “SampleDataBindChart“.
On Form1, open code window and import these libraries. The first two libraries are used for SQL. The last one is used for Chart.
```
Imports System.Data
Imports System.Data.SqlClient
 
Imports System.Windows.Forms.DataVisualization.Charting
```

Type code below on Form1_Load().

        Dim strConn As String = "Data Source=BKKSQL001\INSTANCE01;" & _
            "Initial Catalog=Northwind;Integrated Security=True"
 
        Dim conn As New SqlConnection(strConn)
 
        Dim sqlProducts As String = "SELECT Top 8 ProductName, UnitsInStock FROM Products"
        Dim da As New SqlDataAdapter(sqlProducts, conn)
        Dim ds As New DataSet()
        da.Fill(ds, "Products")
 
        Dim ChartArea1 As ChartArea = New ChartArea()
        Dim Legend1 As Legend = New Legend()
        Dim Series1 As Series = New Series()
        Dim Chart1 = New Chart()
        Me.Controls.Add(Chart1)
 
        ChartArea1.Name = "ChartArea1"
        Chart1.ChartAreas.Add(ChartArea1)
        Legend1.Name = "Legend1"
        Chart1.Legends.Add(Legend1)
        Chart1.Location = New System.Drawing.Point(13, 13)
        Chart1.Name = "Chart1"
        Series1.ChartArea = "ChartArea1"
        Series1.Legend = "Legend1"
        Series1.Name = "Series1"
        Chart1.Series.Add(Series1)
        Chart1.Size = New System.Drawing.Size(800, 400)
        Chart1.TabIndex = 0
        Chart1.Text = "Chart1"
 
        Chart1.Series("Series1").XValueMember = "ProductName"
        Chart1.Series("Series1").YValueMembers = "UnitsInStock"
 
        Chart1.DataSource = ds.Tables("Products")

Code Explanation:

Line 1-2: Define a connection string to connect to a database on SQL Server.
- Data Source is a SQL Server name.
- Initial Catalog is a database name.
- Set Integrated Security=True to use the current user as identity to access the SQL Server database.
Line 4: Create a SqlConnection’s object.
Line 6: Define SQL query string.
Line 7-9: Execute the query and populate result to DataSet’s object.
Line 11-14: Create Chart’s objects.
Line 15: Add Chart’s object to the form.
Line 17-29: Set Chart’s properties (ChartArea, Legend and Series).
Line 31-32: Bind column “ProductName” to X-axis and column “UnitsInStock” to Y-axis on the “Series1” Chart.
Line 34: Set Chart’s data source to the DataTable in the DataSet’s object.

Run the project. You see a chart displaying “Product Name” on X-axis and “Unit in Stock” on Y-axis which data is gathered from Northwind database on SQL Server.

Creating Graph with VB.NET, Part 2: Customize Chart

linglom — Fri, 14 May 2010 07:45:20 +0000

On Part 1: Basic Chart, I show how to create a basic chart with default chart type and color style. Now you will see how to customize those properties on a chart.

Sample chart

The sample chart that I use on this post has a series “Series1” which has 3 data points “10,20,30“.

Change chart type

There are many chart types that you can select for Chart control. On this example, I show some of those chart types which are Point, Line, Bar, Pie.

On Chart Properties, click the Series collection. Then, click the ellipsis button.
On Series Collection Editor, select “Series1” in the Members area and change the Chart type property to Point.
The Point chart type.
The Line chart type.
The Bar chart type.
The Pie chart type.

Change Color style of chart

There are many color palettes that you can choose for Chart control. This section shows how to change color of Chart control.

On Chart Properties, click on Palette property. You see a drop down button. Click on it and you can choose a color palette for your chart.
The example below is Bright color palette.

Insert title to chart

This section shows how to insert title to Chart control.

On Chart Properties, click the Title collection. Then, click the ellipsis button.
On Title Collection Editor, click Add and set (Text) to “My Sample Chart” in the newly created Title object.
Run the project. You will see a title on top of the chart.
You can customize title’s text style, title position, title color on title properties.

3D chart

This section shows how to use three-dimensional (3D) chart areas in Chart control.

On Chart Properties, click the ChartAreas collection. Then, click the ellipsis button.
On ChartArea Collection Editor, select “ChartArea1“. Expand Area3DStyle and change (Enable3D) to True.
Note: You can customize your 3D Style on this Area3DStyle properties .
You see the chart is now 3D.

Creating Graph with VB.NET, Part 1: Basic Chart

linglom — Tue, 11 May 2010 04:21:33 +0000

This series shows how to create chart or graph with VB.NET using Microsoft Chart Controls for .NET Framework.

I divide the series into 3 parts:

Creating Graph with VB.NET, Part 1: Basic Chart
Creating Graph with VB.NET, Part 2: Customize Chart
Creating Graph with VB.NET, Part 3: Data Binding Chart to Database

On this post, you will learn how to create a basic chart on Windows Form Application with VB.NET. I use Microsoft Visual Studio 2005 as IDE.

Requirement

Microsoft Visual Studio 2005 or later.
.NET Framework 3.5 SP1 or later. You can download Microsoft .NET Framework 3.5 Service Pack 1 from Microsoft website.
Microsoft Chart Controls for Microsoft .NET Framework 3.5

Step-by-step

Install the requirement software as stated on the Requirement section.
Open Microsoft Visual Studio 2005. Create a new VB.NET’s Windows Application. Type the name of the project as “SampleBasicChart“.
On Toolbox window, drag a Chart control from the Data category to the Windows Form.

Note: If you does not see the Chart control in the Toolbox, you need to perform these steps below:
- Right-click on the Toolbox window and select Choose Items.
- On Choose Toolbox Items, click Browse.
- Browse to the location where you have installed Microsoft Chart Controls. The default location is
  C:\Program Files\Microsoft Chart Controls\Assemblies and select System.Windows.Forms.DataVisualization.dll. Then, click Open.
- You see Chart control has been added to .NET Framework Components. Verify that its check box is checked and click OK.
On Chart Properties, you see an empty chart with a default series, “Series1“. Next, I’m going to add another Series. On Chart Properties, click the Series collection. Then, click the ellipsis button.
On Series Collection Editor, click Add. You will see “Series2” has been added to the collection.
Now you have two series on a chart. But there is not any data on the chart so I will add some example data point on each series. Select Series1 and click the ellipsis button on Points collection.
On Series Collection Editor, select “Series1” in the Members area and click the Points collection property. Then, click the ellipsis button.
On DataPoint Collection Editor, click Add and assign a value “10” to the YValues property in the newly created DataPoint object.
Repeat step 8 to add two more DataPoint object with values “20” and “30” repectively. Then, click OK to close the DataPoint Collection Editor window.
Note: These values are example values, you may use any value as you want.
Repeat step 7-9 again on “Series2” with YValues as you want. Then, click OK to close the Series Collection Editor windows.
Run the project. You see the chart with two series as you created.

Accessing MySQL on VB.NET using MySQL Connector/Net, Part VIII: Display Result on GUI

linglom — Fri, 29 May 2009 15:29:56 +0000

Introduction

Actually, I don’t prepare to write this post while I was writing the series. But there are some people want to know how to display a query data on Windows form rather than in console window which I wrote in the previous post. So this post, I’ll show how to display a query data on DataGridView on Windows form using MySqlDataAdapter.

You can see index of this series at Accessing MySQL on VB.NET using MySQL Connector/Net, Part I: Introduction

Section

Step-by-step
Download Code
Summary

Step-by-step

I’ll continue from the previous post. You can download a project file from the previous post at here – SampleMySQL (zip format). The project was created on Microsoft Visual Studio 2005.
Open the Design view of Form1.
Drag DataGridView tool from the Toolbox window to empty area on the form.
Note: If you can’t find Toolbox window, select View -> Toolbox.
The DataGridView is placed on the form. The dark background indicates the area of DataGridView’s object. On Properties window, you see the default name is DataGridView1.
Back to the Form’s code view. Comment all the lines in Form1_Load method. These are the code from the previous post which I don’t want it to be executed.

Copy the code below to the form as a new method. Notice that this method is similar to retriveData() method except that it use MySqlDataAdapter rather than MySqlDataReader.

Public Sub retriveDataToDataGrid()
        Try
            Dim query As String = "SELECT * FROM Country"
            Dim connection As New MySqlConnection(connStr)
            Dim da As New MySqlDataAdapter(query, connection)
            Dim ds As New DataSet()
 
            If da.Fill(ds) Then
                DataGridView1.DataSource = ds.Tables(0)
            End If
 
            connection.Close()
 
        Catch ex As Exception
            Console.WriteLine(ex.Message)
        End Try
End Sub

Code Explanation:

Line 3-5: Create New MySqlDataAdapter object with some parameters.
Line 6: Create an empty data set.
Line 8-10: Fills a data set and set data source of DataGridView1 to a table in the data set.
Line 12: Close the connection.

Add code to the Form1_Load method to call retriveDataToDataGrid() when the form is loaded.
Run the project. You’ll see the result on DataGridView on Windows form. You may adjust the size of DataGridView to suit your screen.

Download Code

You can download a complete project file at here – SampleMySQL2. The project was created on Microsoft Visual Studio 2005.
Back to top

Summary

Now you have reach the end of the article. After 8 parts, you should be able to develop an simple application to access MySQL Server on your own. I think that the article is quite clear than other accessing database server articles that I wrote last year. If you have any question, feel free to leave a comment below.

Reference

Using MySqlDataAdapter on dev.mysql.com

Accessing MySQL on VB.NET using MySQL Connector/Net, Part VII: Perform SQL Operations

linglom — Wed, 18 Mar 2009 01:57:19 +0000

Perform SQL Operations

From the previous part, I have successfully connect to world database on MySQL Server from VB.NET. Next, I try to perform basic SQL operations (SELECT, INSERT, UPDATE and DELETE) on the world database.
Note: This post is continued from the previous part. If you start a new project, you’ll need to add MySql.Data reference. See the previous post for more detail.

You can see index of this series at Accessing MySQL on VB.NET using MySQL Connector/Net, Part I: Introduction

Section

Declare a Connection String
Retrieve Data from Database
Update Record on Database
Download Code
Summary

Declare a Connection String

If you continue from the previous part, you simply move the connStr variable from TestConnection() method to global scope. Otherwise, declare a new global variable as connection string with the value below.
Note: For more detail about how to build a connection string, see the previous post.

Private connStr As String = "Database=world;" & _
                    "Data Source=192.168.125.21;" & _
                    "User Id=worldUser;Password=worldpassword;" & _
                    "Connection Timeout=20"

The code will look similar as the figure below.

Back to top

Retrieve data from database

To retrieve data from MySQL, I’ll use MySqlDataReader Class from MySql.Data library. First, I open the connection to the world database on MySQL Server. Then, executes the query command by using ExecuteReader method and assigns to MySqlDataReader object. After that, looping on MySqlDataReader object to get result. Let’s see the code below.

Public Sub retriveData()
        Try
            Dim query As String = "SELECT * FROM Country"
            Dim connection As New MySqlConnection(connStr)
            Dim cmd As New MySqlCommand(query, connection)
 
            connection.Open()
 
            Dim reader As MySqlDataReader
            reader = cmd.ExecuteReader()
 
            While reader.Read()
                Console.WriteLine((reader.GetString(0) & ", " & _
                    reader.GetString(1)))
            End While
 
            reader.Close()
            connection.Close()
        Catch ex As Exception
            Console.WriteLine(ex.Message)
        End Try
End Sub

Code Explanation:

Line 21: Create a query variable as string.
Line 22: Create a MySQLConnection object with the defined connection string in global as parameter.
Line 23: Create a MySQLCommand object with previous 2 variables as parameters.
Line 25: Open a connection to MySQL Server using the defined connection string.
Line 27-28: Call ExecuteReader() method and assign the result to MySqlDataReader
object.
Line 30-33: Looping on MySqlDataReader object to get results to the console.
Line 35-36: Close the reader and connection. I recommend to close these objects after using everytime.
Line 38: If there is any error in the method, send to console.

The code will look similar as the figure below.

The result of the query shows the first and second columns in the output window.

Back to top

Update Record on Database

Coding on INSERT, UPDATE and DELETE SQL operations are identical except only sql command that is executed. When I perform these operations to database, there is no need to get records from the database. So I use ExecuteNonQuery() Method from MySqlCommand Class. For INSERT, UPDATE and DELETE statements, the return value is the number of rows affected by the command. For all other types of statements, the return value is -1.
Note: You can use ExecuteNonQuery to perform any type of database operation, however any result sets returned will not be available.

Update Function

This function accepts a parameter as sql command and send to execute on MySQL Server. So the function can be use for INSERT, UPDATE and DELETE operations also any operation that doesn’t need a return result sets. Also, it returns an integer value of affected rows.

Function updateRecord(ByVal query As String) As Integer
        Try
            Dim rowsEffected As Integer = 0
            Dim connection As New MySqlConnection(connStr)
            Dim cmd As New MySqlCommand(query, connection)
 
            connection.Open()
 
            rowsEffected = cmd.ExecuteNonQuery()
 
            connection.Close()
 
            Return rowsEffected
        Catch ex As Exception
            Console.WriteLine(ex.Message)
        End Try
End Function

Code Explanation:

Line 50: The code is similar to retrieve data section only it call ExecuteNonQuery() method and the return value is affected rows.

The function code will look similar as the figure below.

Example INSERT

To execute INSERT command, try the statement below. The sql command will insert a new record to Country table on world database. Then, output the affected rows to console.

14	Console.WriteLine(updateRecord("INSERT INTO Country (Code, Name) VALUES ('AAA','Test Name')"))

Example UPDATE

The UPDATE command belows change Name to ‘Test2′ on row which has code = ‘AAA’. And output the affected rows to console.

15	Console.WriteLine(updateRecord("UPDATE Country SET Name='Test2' WHERE Code ='AAA'"))

Example DELETE

The DELETE command deletes a record which has code equals ‘AAA’. And output the affected rows to console.

16	Console.WriteLine(updateRecord("DELETE FROM Country WHERE Code ='AAA'"))

When I have run the application with the 3 statements above, the output window shows the row affected of each statement as the figure below.

Back to top

Download Code

You can download a complete project file at here – SampleMySQL (zip format). The project was created on Microsoft Visual Studio 2005.
Back to top

Summary

Now you have reach the end of the article. After 7 parts, you should be able to develop an simple application to access MySQL Server on your own. I think that the article is quite clear than other accessing database server articles that I wrote last year. If you have any question, feel free to leave a comment below.
Back to top

Accessing MySQL on VB.NET using MySQL Connector/Net, Part VI: Create Connection

linglom — Fri, 13 Mar 2009 14:40:59 +0000

Create Connection

After I have prepared many things for showing how to access MySQL Server using VB.NET. Let’s see what I have done so far. Right now, I have a remote MySQL Server at 192.168.125.21 with port 3306 (Default port). Also, a sample database “world” and a user account “worldUser” with password “worldpassword”. Now it’s time to start Microsoft Visual Studio 2005 on a development PC.

You can see index of this series at Accessing MySQL on VB.NET using MySQL Connector/Net, Part I: Introduction

Create Connection

On Development PC, open Microsoft Visual Studio 2005.
Create a New Windows Application Project “SampleMySQL”.
First, I need to add a MySQL library. Right-click on the project name (SampleMySQL) -> Add Reference.
On Add Reference, select MySQL.Data on .NET tab.
By default, the reference library (MySQL.Data) won’t be copied to the output directory. That means when you deploy the application on other PC which doesn’t have the library installed, it’ll throw error. So I have to set the Copy Local property of the library file to True. Click Show All Files icon.
Expand References -> Select MySQL.Data -> Change Copy Local property to True.
Now it’s time to coding the application. First, I have to import a namespace. Open the Code View and add this line on the top.
```
Imports MySql.Data.MySqlClient
```

Add these code to the Class.

    Private Sub Form1_Load(ByVal sender As System.Object, _
            ByVal e As System.EventArgs) Handles MyBase.Load
        TestConnection()
    End Sub
 
    Public Sub TestConnection()
        Try
            Dim connStr As String = "Database=world;" & _
                    "Data Source=192.168.125.21;" & _
                    "User Id=worldUser;Password=worldpassword"
            Dim connection As New MySqlConnection(connStr)
            connection.Open()
            connection.Close()
            MsgBox("Connection is okay.")
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    End Sub

Code Explanation:

Line 1-4: Simple Form_Load event that call TestConnection() method. The method is invoked when the form is loaded.
Line: 7-17: Try-Catch scope. If there is any error in try scope, throws exception and goes to catch scope.
Line: 8-10: A connection string represents configuration for connect to MySQL Server. Common attributes are:
1. Database. The database to be used after a connection is opened.
2. Data Source. The name of the MySQL server to which to connect.
3. Port. The port MySQL is using to listen for connections. The default value is 3306
4. User ID. The user that use to connect to the database on MySQL Server
5. Password. Password of the user.
6. Connection Timeout. Time to wait while trying to establish a connection before terminating the attempt and generating an error.
Line 11: Create MySqlConnection object and assign connectionString property.
Line 12-13: Test open and close the connection to the database on MySQL Server.
Line 14: If there is no error, show a success message.
Line 16: Show the error message.

Next, test the code by run the application. If the connection is successfully connected and disconnected. You’ll see the message “Connection is okay”.
If something wrongs, you’ll see message other than the previous step. The figure below is the example that mistyped the database name in the connection string.

Accessing MySQL on VB.NET using MySQL Connector/Net, Part V: Install MySQL Connector Net

linglom — Fri, 06 Mar 2009 03:00:47 +0000

Install MySQL Connector Net

From last 4 parts, I have prepared MySQL Server with sample database. I’ve done on a database PC. Next, I’ll move to a development PC. Assume that I have already installed Microsoft Visual Studio 2005 already. Now I need to download and install MySQL Connector/Net 5.2 on a Development PC which is a library for connect to MySQL Server from .NET Application.

You can see index of this series at Accessing MySQL on VB.NET using MySQL Connector/Net, Part I: Introduction

Setup MySQL Connector Net 5.2.5

Download MySQL Connector/Net 5.2 from mysql.com.
Extract the downloaded file “mysql-connector-net-5.2.5.zip” on a Development PC.
Execute the downloaded file “MySql.Data.msi”. On Setup Welcome Screen, click Next.
On Choose Setup Type, click on Typical.
On Ready to install MySQL Connector Net 5.2.5, click Install.
When Setup has completed, click Finish.
You can view the document of MySQL Connector Net 5.2.5 from Start -> Programs -> MySQL -> MySQL Connector Net 5.2.5 -> Documentation.
This is the screen shot of documentation.

Accessing MySQL on VB.NET using MySQL Connector/Net, Part IV: Create & Grant MySQL User Account

linglom — Sat, 28 Feb 2009 15:57:33 +0000

Create & Grant MySQL User Account

By default, the root account on MySQL Server has all privileges on every tables on MySQL Server but only localhost can have accessed (remote access is not allowed) and it is recommend to use other user account rather than root account to perform operations on MySQL Server (for security issue). Therefore, you should create a new user account on MySQL and grant at least privileges for the account as possible.

You can see index of this series at Accessing MySQL on VB.NET using MySQL Connector/Net, Part I: Introduction

This post, I’m going to show how to create a new user account “worldUser” on MySQL Server and grant privileges to the user account. Mostly usage privileges are SELECT, INSERT, DELETE and UPDATE. Also, I’ll allow remote connection from any host so that I can develop an application from remote PC to the database PC.
Note: If you are in development in a single environment, it’s OK to use root account. But Don’t in production.

Section

Create New MySQL User Account
Grant Privileges on User Account

Create New MySQL User Account

On the Database PC, connect to MySQL Server. Open Command-line and type
```
mysql -u root -p
```
It’ll ask for the password. Type root’s password.
To Create a User Account on MySQL Server, use this format:
```
CREATE USER username IDENTIFIED BY 'password'
```
I’ll create MySQL User Account “worldUser” with password “worldpassword”. I use this account to connect to MySQL Server from remotely PC in later post.
```
CREATE USER worldUser IDENTIFIED BY 'worldpassword';
```

Grant Privileges on User Account

To grant privileges on MySQL User Account, use this format:
```
GRANT privileges ON database.table TO 'username'@'host'
```
I’m going to grant privileges on “worldUser” to allow SELECT, INSERT, UPDATE and DELETE on world database from any machine.
```
GRANT SELECT,INSERT,UPDATE,DELETE ON world.* TO 'worldUser'@'%';
```
Another grant example. Grant SELECT privilege to mysql.proc on the certain user. This is not required to run, just an example.
```
GRANT SELECT ON mysql.proc TO 'worldUser'@'%';
```

Accessing MySQL on VB.NET using MySQL Connector/Net, Part III: Install Sample Database

linglom — Mon, 23 Feb 2009 03:36:45 +0000

Install Sample Database

You can download example databases for MySQL at http://dev.mysql.com/doc (Scroll down to Example Databases section). By the time I’m writing the article, there are 4 sample databases available on the page. I choose the world database since it compatible with all MySQL version.

You can see index of this series at Accessing MySQL on VB.NET using MySQL Connector/Net, Part I: Introduction

Install Sample Database

Download the sample database “world database”. Extract it, you’ll get the world.sql file to the Database PC. This file will be imported to MySQL in few steps later.
On the database PC, open command-line mode. Type below command to connect to the MySQL Server using MySQL’s root account.
```
mysql -u root -p
```
The parameter -p makes MySQL ask you to enter the password. Then, type the root’s password. In this example, it is “password”.
Note: You can type this command on any path because I have added MySQL path to system environment while I was configuring MySQL Server on the previous part.
Now I have connected to the MySQL Server. Next, I’m going to create an empty database name “world”.
```
CREATE DATABASE world;
```
Then, change the default database to the created database.
```
USE world;
```
Next, load the contents of “world.sql” file into the world database. The “world.sql” file was created on the first step.
```
SOURCE c:world.sql
```
You have to alter the path to where the world.sql file is located.
You’ll see lot of output that MySQL performs query from the world.sql file.
After MySQL finishes processing the world.sql file, try to test if the query is executed successfully. Type the command below to list all tables on the current database.
```
SHOW TABLES;
```
You’ll see that there are 3 tables.
You also can see the columns on the table by type the below command.
```
DESCRIBE Country;
```
If you see the columns and tables as previous steps, it means that you have install sample database successfully.

Reference

Setting Up the world Database – MySQL.com.

Accessing MySQL on VB.NET using MySQL Connector/Net, Part II: Setup MySQL Server

linglom — Tue, 17 Feb 2009 14:41:41 +0000

Setup MySQL Server

This section I’ll show how to setup MySQL Server on a database PC. You can see index of this series at Accessing MySQL on VB.NET using MySQL Connector/Net, Part I: Introduction

Download MySQL 5.1.30 Community Edition from mysql.com.
Double-click the setup file mysql-essential-5.1.30-win32.msi. Click Next.
On Setup Type, select Typical. Click Next.
On Ready to Install the Program, click Install.
On Wizard Completed, check Configure the MySQL Server Now and click Finish.
On MySQL Configuration Wizard, click Next.
On MySQL Server Instance Configuration, select Standard Configuration.
Note: If you want to develop in a single PC environment, you can select Detailed Configuration instead and choose Developer Machine so MySQL Server won’t consume too much resource on the PC.
On MySQL Server Instance Configuration, verify that all check boxes are checked on this page and click Next. The first and second (Install As Windows Service and Launch the MySQL Server automatically) check boxes configure MySQL as a Windows service so that you don’t have to login to the PC and start MySQL Server manually, it’ll start when the PC is on automatically.
On MySQL Server Instance Configuration, check only the upper check box Modify Security Settings and enter the root password. The root user is the default user on MySQL who has all privileges on the MySQL Server. In this example, I set the root’s password to “password”. Click Next.
Note: This is just an example, you should set password more complexity than this.
On MySQL Server Instance Configuration, click Execute to start the configuration.
When the configuration is done, click Finish to complete install and configure MySQL Server.