Can't display record that has NULL values

[Michelle Tay]

Hai,
below is part of my code:


Dim query As String = "SELECT * FROM tbluser"
Dim MyConn As New OdbcConnection(MyConString)
MyConn.Open()
Dim MyCommand As New OdbcCommand
MyCommand.Connection = MyConn
MyCommand.CommandText = query

' search target id
While MyDataReader.Read
' target found, stop searching & display record
If (CStr(MyDataReader("user_id")) = id) Then
txtUserFindID.Text = CStr(MyDataReader("user_id"))
txtUserFName.Text = CStr(MyDataReader("user_fname"))
txtUserLName.Text = CStr(MyDataReader("user_lname"))
txtUserPswd.Text = CStr(MyDataReader("user_pwd"))
txtUserPhone1.Text = CStr(MyDataReader("user_phone"))
Exit While
End If
End While


I have a table call tbluser, which contain "user_id(PK), user_fname, user_lname, user_pwd, user_phone". At first, only user_id & user_pwd have values, other are null value. i would like to search the record based on ID & display tat record so that user can fill in other attributes' values. But when i run the code, the error msg state that "cast from type DBNULL to type String is not valid".
it is has any other solution other than hide code checking whether the attribute is Null value of not? coz if like tat i may need to do the checking for 20+ attributes & tis will slow down the performance. cld any body help me??? 10s in advance.