You will need to create table with an integer field with a default of 0.
On form_load you will want to pull the value from the database and add 1 to it.
On form_close you will want to save that value back to the database.
You can use my previous post here for the connection example.
You will do something like this:
'In the form load event.
sqlcmd = "SELECT curnum FROM table"
cmd = new OleDBCommand(sqlcmd,con)
'In the form close event.
sqlcmd = "UPDATE table SET curnum ='" & txtStudentID.text & "'"
cmd = new OleDBCommand(sqlcmd,con)
I am posting this code for anyone who may be having issues with connecting to a database. Feel free to use this code as you wish.
This will be using the OLEDB library.
'Imports
Imports System.Data.OleDb
Public Class Form1
'Declarations
Dim con As OleDbConnection
Dim cmd As OleDbCommand
Dim sqls As String
Dim sqlcmd As String
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
'In form_load event, but can be used on button click.
'For hard coded connection string
sqls = "Provider=SQLOLEDB;Datasource=YOURSERVERNAMEHERE;" & _
"Initial Catalog=YOURDATABASENAMEHERE;Integrated Security=SSPI"
'For dynamic connection string
sqls = "Provider=SQLOLEDB;Datasource=" & txtServerName.Text & ";Initial Catalog=" & _
txtDatabaseName.Text & ";Integrated Security=SSPI"
'Place all connection code in try/catch blocks.
Try
'Connect using the string we have just created
If con.State <> ConnectionState.Open Then
con.ConnectionString = sqls
con.Open()
End If
'Alternative way is:
If con.State <> ConnectionState.Open Then
con = New OleDbConnection(sqls)
con.Open()
End If
'Selecting everything from a database
sqlcmd = "SELECT * FROM tablename"
'Selecting a specific value when you have a reference
sqlcmd = "SELECT * FROM tablename WHERE columnname = referencevalue"
'Non hardcoded method
sqlcmd = "SELECT * FROM tablename WHERE columnname = '" & txtDataToSearchBy.Text & "'"
'Setting the command
cmd.Connection = con
cmd.CommandText = sqlcmd
'Alternative way is:
cmd = New OleDbCommand(sqlcmd, con)
'Querying the database
'Many differny ways.
'Returns number of rows
cmd.ExecuteNonQuery()
'Returns only the first column of first row.
cmd.ExecuteScalar()
'Builds a data reader with the current command.
cmd.ExecuteReader()
'Good …
Reverend Jim commented: Nice, simple, straightforward example.+8
'sqls is a string
'cmd is a command builder
sqls = "SELECT * FROM employees WHERE id = '" & textbox1.text & "'"
cmd = New CommandBuilder(sqls,connection)
If cmd.ExecuteNonQuery = False Then
MsgBox("ID not found")
End If
The code above creates a structure, in the form of a class, then passes the string information into the class. It then builds the string and assigns the value to your settings with what ever string name you want it to be.
Then it saves.
To use this, build the class by using the Project > Add Class name it ClassConnectionBuilder. Save the code you have above into that class.
'Creating connection string
Imports System.Data.SqlClient
Public Class ClassConnectionBuilder
Public Shared Function ConnectionStringBuilder(ByRef Server As String, ByRef database As String, _
ByRef userid As String, ByRef password As String) As String
Dim sqlConnString As New System.Data.SqlClient.SqlConnectionStringBuilder() With {
.DataSource = Server,
.InitialCatalog = database,
.UserID = userid,
.Password = password
}
Return sqlConnString.ConnectionString
End Function
End Class
Then you can use the build by either importing it then using it or providing a full "path".
IE
'Imported
'Importing would be: Imports yourprojectname.ClassConnectionBuilder
SqlConnectionStringBuilder(string,string,string,string)
'Not imported
ClassConnectionBuilder.SqlConnectionStringBuilder
If you are wanting ID's to be unique, you might want to think about making it a primary key. Thus making it not possible to have multiples. Then you can wrap your insert in a try catch, the client will handle the "No duplicate keys" message.
You could also write a tiny app with a text box. The user puts the sql command in the text box and presses a button. The button will fire off code that will bind the text string to a command and ExecuteNonQuery.
The above suggestion is correct, The program might also be terminating to fast for you to see.
Try wrapping the program with a while.
Like this:
Sub Main()
Dim uservalue As String
Dim ex As String = ""
While ex <> "exit"
Console.WriteLine("What football team do you support? Oldham, Manchester City, or Manchester United?")
uservalue = Console.ReadLine()
If uservalue = "oldham" Then
Console.WriteLine("Good lad latics!")
ElseIf uservalue = "Manchester City" Then
Console.WriteLine("BOOOOOOOOOOOOOOOOO!!!!")
ElseIf uservalue = "Manchester United" Then
Console.WriteLine("BOOOOOOOOOOOOOOOOO!!!!")
Else
Console.WriteLine("I DONT KNOW WHO YOU ARE!")
End If
Console.WriteLine("Type exit to exit the application")
ex = Console.ReadLine()
End While
End Sub
This allows you to loop through the program until you want to exit.
I have done as you have said above, but my only problem is that I need sql server native client to be bootstrapped too. Anyone know how to do this?
I have abandoned Inno Setup and I am using Install Shield. I have created the setup solution and added the files that are prerequisets, but how do I make it install when they are not present?
I have already used the new requirement wizard, the only thing you can do there is check if it is there, if not prompt the user.
I need to know how to force install if it doesn't exist on user's machine.
I have recently written a VB.NET application and I am stuck on the deployment.
I can't use the ClickOnce, because the program has to be installed on the machine under program files, therefore, I use InnoSetup.
My problem is that the application requires sqlclient and .net 4.0 to be installed, and I am EXTREMELY green to InnoSetup scripts.
Does anyone know how to make InnoSetup check to see if they are installed, if not install them without prompting the user?
I have searched high and low and can't find a relevent article to my needs. Some are for online downloading, when I need local downloading only, and others are for runtimes.
I just can't seem to find an article that shows how to install automaticly and silent.
Public Class Form1
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
Form2.Show()
Form2.TextBox1.Text = Me.TextBox1.Text 'Where Me references Form1 - the TextBox1 from Form1
End Sub
End Class
Will will loop through the array. Comparing the current index with the next index. Whichever index is higher, you will need compare to the value stored in the temporary variable. If the value in the temp variable is higher, keep it. If not, then write the higher value in the temp.
What Jim is saying is correct. You will have to clear the list every time you change the combo box. That way you have a "fresh piece of paper" to load the new data back on.
If you wanted to limit the number of spaces, you can use Kothaisaravan's method, and incrememnt a counter every time they press the space bar. Then use an if statement with the counter = number and use the replace.
