How to retrieve data from database and put it into text box...

Actually, I am doing about a search function. Users enter customer ID (which is auto number in Access file) and then find the customers, then show the details in the text box. However, I cannot do that because some reasons like references problem ...etc. ---Here is the code-- Public Class Customer Inherits System.Windows.Forms.Form Private connection As OleDbConnection Private command As OleDbCommand Private adapter As OleDbDataAdapter Private Sub btnM_Search_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnM_Search.Click connection.Open() Dim dt As New DataTable adapter = New OleDbDataAdapter(GetAll, connection) command.Connection = connection command.CommandText = "SELECT * FROM tblCustomer WHERE customer_ID = _ @customer_id " command.Parameters.Add("@customer_id", txtM_Item.Text) adapter.Fill(dt) txtM_CustomerID.DataBindings.Clear() txtM_CustomerName.DataBindings.Clear() txtM_phone.DataBindings.Clear() txtM_CustomerID.DataBindings.Add("Text", dt, "customer_ID") txtM_CustomerName.DataBindings.Add("Text", dt, "customer_name") txtM_phone.DataBindings.Add("Text", dt, "phone") connection.Close() End Sub --- end of code --- Thank you very much

You're not creating your objects. Are you doing this somewhere else in the code? You mention reference problems and such, so I'll assume that you're not. You should post exact error messages. Errors are there to tell you what the problem is, not just to annoy you. They shouldn't be ignored. Can you also identify which line has the problem? Tghere may be multiple, but you can wipe them out one at a time. 'create the connection first! connection = new OleDbConnection(); 'set the connection string, too! (this one is for mssql database) connection.ConnectionString = "provider=sqloledb.1;user id=sa;password=mypassword;data source=server1;initial catalog=master"; connection.Open() Dim dt As New DataTable adapter = New OleDbDataAdapter(GetAll, connection) 'create the command object first! command = new OleDbcommand(); command.Connection = connection command.CommandText = "SELECT * FROM tblCustomer WHERE customer_ID = _ @customer_id " I also don't see a GetAll command object, but that's what you're assigning to the selectcommand of your dataadapter. Should your adapter construction look like this instead? adapter = New OleDbDataAdapter(command, connection)

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spgilmore22y ago
You're not creating your objects. Are you doing this somewhere else in the code? You mention reference problems and such, so I'll assume that you're not. You should post exact error messages. Errors are there to tell you what the problem is, not just to annoy you. They shouldn't be ignored. Can you also identify which line has the problem? Tghere may be multiple, but you can wipe them out one at a time. 'create the connection first! connection = new OleDbConnection(); 'set the connection string, too! (this one is for mssql database) connection.ConnectionString = "provider=sqloledb.1;user id=sa;password=mypassword;data source=server1;initial catalog=master"; connection.Open() Dim dt As New DataTable adapter = New OleDbDataAdapter(GetAll, connection) 'create the command object first! command = new OleDbcommand(); command.Connection = connection command.CommandText = "SELECT * FROM tblCustomer WHERE customer_ID = _ @customer_id " I also don't see a GetAll command object, but that's what you're assigning to the selectcommand of your dataadapter. Should your adapter construction look like this instead? adapter = New OleDbDataAdapter(command, connection)
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