C# Windows forms - Data Conduit to connect to a windows form app - windows-forms-designer

Question

Hi guys I need some help with this dataconduit. Its written by my tutor and we used it on a web development project. I am trying to use it for a windows forms application to connect to the database but i get the following error:
An attempt to attach an auto-named database for file C:\Users.... failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.
The data conduit works indeed if i use it on a asp.net website but not on a windows forms
i did try to researched but no luck.
I am just testing it with two text box and a save button
thank you
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data.SqlClient;
using System.Data.OleDb;
using System.Data;
///This class uses the ado.net sql classes to provide a connection to an sql server database.
///it is free for use by anybody so long as you give credit to the original author i.e me
///Matthew Dean mjdean#dmu.ac.uk De Montfort University 2011
//you will need to modify the name of the namespace to suit your own program.
namespace MyClassLibrary
{
public class clsDataConduit
{
//connection object used to connect to the database
SqlConnection connectionToDB = new SqlConnection();
//data adapter used to transfer data to and from the database
SqlDataAdapter dataChannel = new SqlDataAdapter();
//ado.net class for building the sql commands
SqlCommandBuilder commandBuilder = new SqlCommandBuilder();
//stores a list of all of the sql parameters
List<SqlParameter> SQLParams = new List<SqlParameter>();
//data table used to store the results of the stored procedure
DataTable queryResults = new DataTable();
//data row used to store the data for a new record
DataRow newRecord;
//string variable used to store the connection string
private string connectionString;
public clsDataConduit()
{
//this is the constructor for the class
//you will need to modify this to suit your own database name and folder structure
//
//variable to store the patth to the database
string DbPath;
//variable to store the partial path and file name of your database
//modify this line to suit your own needs
string DatabaseName = "\\MyDatabase\\NamesData.mdf";
//set the DbPath concatenating the name of your database
DbPath = GetParentPath() + DatabaseName;
//build up the connection string for the sql server database
connectionString = "Data Source=.\\SQLEXPRESS;AttachDbFilename=" + DbPath + ";Integrated Security=True;User Instance=True";
}
private string GetParentPath()
///this function returns the path to the parent folder of the solution
{
//get the folder for the project
string DbPath = System.AppDomain.CurrentDomain.BaseDirectory;
//variable to store the position of the \\ characters
int Posn;
//loop through the path twice
for (int Counter = 0; Counter != 2; Counter++)
{
//find the right most instance of \\
Posn = DbPath.LastIndexOf("\\");
//split the path at that point
DbPath = DbPath.Substring(0, Posn);
//do it one more time
}
//return the new path
return DbPath;
}
public void AddParameter(string ParamName, string ParamValue)
///public method allowing the addition of an sql parameter to the list of parameters
///it accepts two parameters the name of the parameter and its value
{
//create a new instance of the sql parameter object
SqlParameter AParam = new SqlParameter(ParamName, ParamValue);
//add the parameter to the list
SQLParams.Add(AParam);
}
public void Execute(string SProcName)
{
///public method used to execute the named stored procedure
///accepts one parameter which is the name of the stored procedure to use
//open the stored procedure
//initialise the connection to the database
connectionToDB = new SqlConnection(connectionString);
//open the database
connectionToDB.Open();
//initialise the command builder for this connection
SqlCommand dataCommand = new SqlCommand(SProcName, connectionToDB);
//add the parameters to the command builder
//loop through each parameter
for (int Counter = 0; Counter < SQLParams.Count; Counter += 1)
{
//add it to the command builder
dataCommand.Parameters.Add(SQLParams[Counter]);
}
//set the command type as stored procedure
dataCommand.CommandType = CommandType.StoredProcedure;
//initialise the data adapter
dataChannel = new SqlDataAdapter(SProcName, connectionToDB);
//set the select command property for the data adapter
dataChannel.SelectCommand = dataCommand;
//use the copmmand builder to generate the sql insert delete etc
commandBuilder = new SqlCommandBuilder(dataChannel);
//fill the data adapter
dataChannel.Fill(queryResults);
//get the structure of a single record
newRecord = queryResults.NewRow();
//close the connection
connectionToDB.Close();
}
public void WriteToDatabase()
//void method that updates changes to the data adapter thus changing the database
{
//update any changes
dataChannel.Update(queryResults);
}
public DataRow NewRecord
///this method provides access to the new record as a single data row
{
get
{
//return the blank data row
return newRecord;
}
}
public void RemoveRecord(int Index)
//void method that removes a record at a specified index in the query results
{
//remove the record
queryResults.Rows[Index].Delete();
}
public void AddToDataTable()
//void method that adds the new record to the table data
{
//add the new record to the table
queryResults.Rows.Add(newRecord);
//re initialise the new record
newRecord = queryResults.NewRow();
}
public int Count
//property that returns the count of records in the query results
{
get
{
//return the count of the query results
return queryResults.Rows.Count;
}
}
public DataTable QueryResults
//public property that provides access to the query results
{
get
{
//return the query results
return queryResults;
}
set
{
//set the query results
queryResults = value;
}
}
}
}
this is the code for my name class.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace MyClassLibrary
{
public class clsName
{
private string firstName;
private string lastName;
public string FirstName
{
get
{
return firstName;
}
set
{
firstName = value;
}
}
public string LastName
{
get
{
return lastName;
}
set
{
lastName = value;
}
}
public void Save()
{
clsDataConduit Names = new clsDataConduit();
Names.Execute("sproc_tblNames_GetAll");
Names.NewRecord["FirstName"] = firstName;
Names.NewRecord["LastName"] = lastName;
Names.AddToDataTable();
Names.WriteToDatabase();
}
}
}

Answer 1

thank you guys but i finally managed to make it work. i am not sure if it is the right way to do it but what u have done is i have commented out the public clsDataConduit() {} method and before this method i have modified the connection string adding the full path of my database as follow: private string connectionString = (#"Data Source=.\SQLEXPRESS;AttachDbFilename=C:\Users...\NamesData.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True");