Edit database in management studio using visual studio c# - c#

I have created a database using SQL Server Management Studio and am now trying to edit that database using Visual Studio Express 2012. I have connected the database to Visual Studio and can see my database but I have not been able to edit the database stored in Management Studio using Visual Studio. I have created a form and am trying to insert what is entered into textbox1 into a specific cell on my database after the user defines the column name and row (using the primary key in my DB) with textbox2 and textbox3. What code can I use to perform this action? So far I have had no luck. Thank you in advance for you help.
This is my current code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.SqlClient;
using System.Data.Sql;
using Microsoft.SqlServer.Server;
using System.Data.Linq;
using System.Data.Linq.Mapping;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
SqlConnection myConnectionString = new SqlConnection("Data Source=Server Catalog=DataBase;Integrated Security=True");
SqlCommand command = new SqlCommand();
private void maskedTextBox1_MaskInputRejected(object sender, MaskInputRejectedEventArgs e)
{
}
private void button3_Click(object sender, EventArgs e)
{
try
{
using (SqlConnection dbConnection = new SqlConnection()) // the "using" construct will close and dispose of the connection
{
dbConnection.ConnectionString = ("Data Source=Server ;Initial Catalog=Database;Integrated Security=True");
dbConnection.Open();
maskedTextBox1.Clear();
dateTimePicker1.Value = DateTime.Now.AddDays(0);
comboBox1.SelectedIndex = -1;
String username = comboBox2.Text;
using (SqlCommand command = new SqlCommand("INSERT INTO [Table Name] (Column Name) VALUES ([Parm1])", dbConnection))
{
command.Parameters.AddWithValue("Parm1", username);
command.ExecuteNonQuery();
}
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}
private void button1_Click(object sender, EventArgs e)
{
this.Close();
}
private void button2_Click(object sender, EventArgs e)
{
//Close the Window
this.Close();
}
private void label4_Click(object sender, EventArgs e)
{
}
private void comboBox1_DataSourceChanged(object sender, EventArgs e)
{
}
private void button4_Click(object sender, EventArgs e)
{
myConnectionString.Open();
MessageBox.Show("Sql is connected");
myConnectionString.Close();
}
}
}

The VALUES clause should specify a parameter and that parameter should be specified when adding the parameter value. Try substituting the following:
String sqlquery = "INSERT INTO [Man Power] ([Person_Performing_Phase_2]) VALUES ([Parm1])";
SqlCommand command = new SqlCommand(sqlquery, con);
command.Parameters.AddWithValue("Parm1", username);
EDIT
Your connection string is incorrectly formed. I believe the following format is appropriate for your current needs:
String myConnectionString = Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;
I would use the following code for inserting data, which opens and closes the connection for each operation. Note the "command.ExecuteNonQuery" statement - its omission is why your insert failed to work - although I am unsure why opening the connection did not throw an error.
private void button3_Click(object sender, EventArgs e)
{
try
{
using (SqlConnection dbConnection = new SqlConnection()) // the "using" construct will close and dispose of the connection
{
dbConnection.ConnectionString = myConnectionString;
dbConnection.Open();
maskedTextBox1.Clear();
dateTimePicker1.Value = DateTime.Now.AddDays(0);
comboBox1.SelectedIndex = -1;
String username = comboBox2.Text;
using (SqlCommand command = new SqlCommand("INSERT INTO [Man Power] ([Person_Performing_Phase_2]) VALUES ([Parm1])", dbConnection))
{
command.Parameters.AddWithValue("Parm1", username);
command.ExecuteNonQuery();
}
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}
You should also remove all other _Click methods and replace the connection and command statement with the myConnectionString assignement.

Related

View data of a database in C# form

I'm new in C# and I don't know how to view data of MySQL in a form. I have already fixed to create a delete button and an add button but now I also want to view that data in the form. I looked up all kinds of things to get it working, but I just can't get it done. Does anyone know what I need to do to get it work?
Here is how I want to view the data: https://i.stack.imgur.com/4Yixa.png
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using MySql.Data.MySqlClient;
namespace Test
{
public partial class Apparatenlijst : Form
{
string MyConnectionString = "Server=localhost;Database=apparatuur;Uid=root;Pwd=;";
public Apparatenlijst()
{
InitializeComponent();
}
private void Apparatenlijst_Load(object sender, EventArgs e)
{
}
private void label2_Click(object sender, EventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
string apparaatt = toevoegg.Text;
MySqlConnection connection = new MySqlConnection(MyConnectionString);
MySqlCommand cmd;
connection.Open();
try
{
cmd = connection.CreateCommand();
cmd.CommandText = "INSERT INTO lijst(apparaatnaam)VALUES(#apparaatnaam)";
cmd.Parameters.AddWithValue("#apparaatnaam", apparaatt);
cmd.ExecuteNonQuery();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{
if (connection.State == ConnectionState.Open)
{
connection.Close();
MessageBox.Show("Apparaat succesvol toegevoegd");
}
}
}
private void button2_Click(object sender, EventArgs e)
{
}
private void textBox2_TextChanged(object sender, EventArgs e)
{
}
private void verwijder_Click(object sender, EventArgs e)
{
string apparaata = verwijderr.Text;
MySqlConnection connection = new MySqlConnection(MyConnectionString);
MySqlCommand cmd;
connection.Open();
try
{
cmd = connection.CreateCommand();
cmd.CommandText = "DELETE FROM lijst WHERE apparaatnaam=#apparaatnaam";
cmd.Parameters.AddWithValue("#apparaatnaam", apparaata);
cmd.ExecuteNonQuery();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{
if (connection.State == ConnectionState.Open)
{
connection.Close();
MessageBox.Show("Apparaat succesvol verwijderd");
}
}
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
}
private void lvStudents_SelectedIndexChanged(object sender, EventArgs e)
{
}
}
}
Are you using ListView to display the data?
You can call method MySqlDataAdapter.Fill() to get the datatable from data source. For this, you need to install Nuget package MySql.Data.
Then traverse the datatable and add new ListViewItem object to the ListView.
string constr = #"connection string";
using (MySqlConnection conn = new MySqlConnection(constr))
{
MySqlDataAdapter sda = new MySqlDataAdapter("Select * From lijst", conn);
DataSet ds = new DataSet();
sda.Fill(ds);
listView1.BeginUpdate();
foreach (DataRow row in ds.Tables[0].Rows)
{
ListViewItem lvi = new ListViewItem();
lvi.Text = row["Field1"].ToString();
lvi.SubItems.Add(row["Field2"].ToString());
lvi.SubItems.Add(row["Field3"].ToString());
listView1.Items.Add(lvi);
}
listView1.EndUpdate();
}

error occored The connection was not closed The connection current state is open

My code is like this : I input the caseid in the textbox and try to click Find button to find the corresponding result. But Visual studio always says :error occored The connection was not closed The connection current state is open.
This is my first time design ADO.NET myself and I need to finish my advisor research tasks.
Could you check the code and tell me what wrong?
Thanks
Sophia
using System;
using System.Data.SqlClient;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace casestudy
{
public partial class Form1 : Form
{
SqlConnection vcon1 = new SqlConnection(#"Data Source=SOPHIA-PC\SQLEXPRESS;Initial Catalog=casestudy;Integrated Security=True");
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
try
{
vcon1.Open();
}
catch (Exception ex)
{
MessageBox.Show("error.occured" + ex.Message);
this.Dispose();
}
}
private void Find_Click(object sender, EventArgs e)
{
string querystring = "SELECT * FROM AssignedSolution WHERE CASEID = #caseid";
SqlCommand Vcom = new SqlCommand(querystring, vcon1);
Vcom.Parameters.AddWithValue("#caseid", txtCASEID);
SqlDataReader rdr = null;
try
{
Vcom.Connection = vcon1;
vcon1.Open();
Vcom.ExecuteNonQuery();
//DataSet vds1 = new DataSet();
rdr = Vcom.ExecuteReader();
//vDa1.Fill(vds1, "res");
//dataGridView1.DataSource = vds1.Tables["res"];
while (rdr.Read())
{
Console.WriteLine(rdr[0]);
}
Vcom.Dispose();
}
catch (Exception ex)
{
MessageBox.Show("error.occured" + ex.Message);
}
finally
{
vcon1.Close();
vcon1.Dispose();
}
}
The connection is being opened on Form1_Load event, then you are trying to open the same connection again in the Find_Click event. You can't open a connection that is already open. Just remove all code from the load event, you don't need it.

Unable to insert row into table using an Oracle Connection

I would like to know what's the problem, or your advice to connect to Oracle. I'm trying with this but when I try to insert values, it doesn't work.
I'm using the Visual Web Developer 2008 and when I add a database on Database Explorer connections, it's working. But when I try to connect via this connection string, it doesn't work. What am I missing?
I don't get an exception, so apparently it's working well. But this code apparently doesn't insert! The id column is a varchar(45). I created the table "test" just for testing purposes.
using System.Data;
using System.Data.OracleClient;
public partial class _Default : System.Web.UI.Page
{
//string oradb = "Data Source=localhost;User ID=root;Password=jesua;Unicode=True;";
String oracle = "User ID=root;Password=jesua;Unicode=True;Data Source=localhost;";
OracleConnection con = new OracleConnection();
public void Conectar() {
try
{
con.Close();
con.ConnectionString = oracle;
con.Open();
}
catch(Exception ex){
throw new Exception("No Conecto " + ex);
}
}
public void desconectar() {
// con.ConnectionString = oracle;
con.Close();
}
public void agregar() {
this.Conectar();
OracleCommand query = new OracleCommand("INSERT INTO testing (id) VALUES ('testing')");
query.ExecuteNonQuery();
desconectar();
}
protected void Button1_Click(object sender, EventArgs e)
{
try {
agregar();
}
catch(Exception ex){
Console.Write("No agrego " + ex);
}
TextBox1.Text = "Conected";
}
}
--------------------------UPDATE------------------
So,
i found the way to do that,
i hope anyone here can use this code in a future...
This code creates the connection betwen Oracle and asp.net C#
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Oracle.DataAccess.Client; // ODP.NET Oracle managed provider
using Oracle.DataAccess.Types;
namespace proyecto
{
public partial class WebForm1 : System.Web.UI.Page
{
public void dbconnect() {
string oradb = "Data Source=localhost;User ID={Yoir ID};Password={Your Password};";
OracleConnection conn = new OracleConnection(oradb); // C#
conn.Open();
OracleCommand cmd = new OracleCommand();
cmd.Connection = conn;
cmd.CommandText = "INSERT INTO TESTING(id) VALUES ('valor')";
int rowsUpdated = cmd.ExecuteNonQuery();
if (rowsUpdated == 0)
Console.Write("Record not inserted");
else
Console.Write("Success!");
conn.Dispose();
}
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{
this.dbconnect();
}
}
}
Good Luck!
The connection string that works for me is
connectionString="Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1522))
(CONNECT_DATA=(SERVICE_NAME=XE)));User Id=system;Password=pass;"
providerName="Oracle.DataAccess.Client"/>
It seems that you are missing the Service Name and Provider Name. You can find the service name in tnsnames.ora file which will be in your installation directory. Also make sure you have installed ODP.NET for Oracle 11g correctly, added reference to the Oracle.DataAccess.dll into your project and add the Provider Name in the connection string.

connecting to database - connectionString connect.Open() error

So I am trying to run a query in a database that searches the database table from a textbox input. My code is
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.SqlClient;
namespace Query
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void employeeBindingNavigatorSaveItem_Click(object sender, EventArgs e)
{
this.Validate();
this.employeeBindingSource.EndEdit();
this.tableAdapterManager.UpdateAll(this.personnelDataSet);
}
private void Form1_Load(object sender, EventArgs e)
{
// TODO: This line of code loads data into the 'personnelDataSet.employee' table. You can move, or remove it, as needed.
this.employeeTableAdapter.Fill(this.personnelDataSet.employee);
}
private void btnExit_Click(object sender, EventArgs e)
{
this.Close();
}
string connectionString = "Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;";
private void btnSearch_Click(object sender, EventArgs e)
{
string commandText = "SELECT employeeID, name, position, hourlyPayRate " +
"FROM dbo.employee WHERE name LIKE '%'+ #Name + '%'";
using (SqlConnection connection = new SqlConnection(connectionString))
{
//Create a SqlCommand instance
SqlCommand command = new SqlCommand(commandText, connection);
//Add the parameter
command.Parameters.Add("#Name", SqlDbType.VarChar, 20).Value = textBox1.Text;
//Execute the query
try
{
connection.Open();
command.ExecuteNonQuery();
}
catch
{
//Handle excepetion, show message to user...
MessageBox.Show("Error bitch!");
}
finally
{
connection.Close();
}
}
}
}
}
When I take the catch out I can see the error occurs at connection.Open(). The error takes a while to happen which makes me wonder whether there is an issue with string connectionString = "Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;";
This is the error that I receive:
An unhandled exception of type 'System.Data.SqlClient.SqlException' occurred in System.Data.dll
You need to validate the connection string. If Open() is throwing an SqlException then the connection string is invalid. To enable you to establish the exact form of the connection string you require, take a look at connectionstrings.com.
As to why the exception is showing as unhanded, you need to 'consume' the exception as follows:
try
{
connection.Open();
command.ExecuteNonQuery();
}
catch (Exception e)
{
// Handle excepetion, show message to user...
MessageBox.Show(e.Message);
}
I hope this helps.
Check this out:
string connectionString = "Server=.\InstanceName;Database=myDataBase;Integrated Security=True;";
Also
string commandText = "SELECT employeeID, name, position, hourlyPayRate
FROM dbo.employee WHERE name LIKE '%#Name%'";
try:
string connectionString = "Data Source=myServerAddress;Initial Catalog=myDataBase;User id=myUser;Password=myPAss;Connect Timeout=15;Integrated Security=false";
Try declaring your connection string inside the event.
An alternate method is to link your database through web.config as follows:
<connectionStrings>
<connectionString="Data Source=(localdb)\v11.0;Initial Catalog=DBName;Integrated Security=True" providerName="System.Data.SqlClient"/>
</connectionStrings>
And then the connection string can be as:
string cs = ConfigurationManager.ConnectionStrings["DBName"].ConnectionString;

How to fix 'System.Data.OleDb.OleDbException'?

first off sorry to ask how to fix this error (i know its a common question) but i am quite new to C# and I cannot seem to find a solution for it.
I am making a windows form that imports data from an excel file and displays it in a DataGridView. When executing I get the error:
"An unhandled exception of type 'System.Data.OleDb.OleDbException'
occurred in System.Data.dll Additional information: No value given for
one or more required parameters."
Here is my code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.OleDb;
using System.IO;
namespace WindowsFormsApplication2
{
public partial class CurrentOrders : Form
{
public CurrentOrders()
{
InitializeComponent();
}
private void CurrentOrders_Load(object sender, EventArgs e)
{
}
private void BackBtn_Click(object sender, EventArgs e)
{
NewOrder NewOrd = new NewOrder();
this.Hide();
NewOrd.Show();
}
private void DataGridViewLOG_CellContentClick(object sender, DataGridViewCellEventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
OleDbConnection conn = new OleDbConnection();
conn.ConnectionString = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\Tombies\Documents\Visual Studio 2013\Projects\WindowsFormsApplication2\WindowsFormsApplication2\PCSsheet.xls" + #";Extended Properties=""Excel 12.0;HDR=Yes;IMEX=1;ImportMixedTypes=Text;TypeGuessRows=0""";
OleDbCommand command = new OleDbCommand
(
"SELECT DATE, CUSTOMER, PO, COMMENTS, PCS FROM [LOG$]", conn
);
DataSet DsOrderLOG = new DataSet();
OleDbDataAdapter Adapter = new OleDbDataAdapter(command);
conn.Open();
Adapter.Fill(DsOrderLOG);
conn.Close();
DataGridViewLOG.DataSource = DsOrderLOG.Tables[0];
}
}
}
I know it has something to do with the 'Adapter.Fill' at the bottom, but from there on I'm lost.
Any help is appreciated!
Date is probably the culprit. Try putting it (an all other column names, for that matter) in brackets:
"SELECT [DATE], [CUSTOMER], [PO], [COMMENTS], [PCS] FROM [LOG$]", conn

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