Insert records into a Microsoft Access database in C #

Question

I am inserting data to access a 2000-2003 format database using C #. When I had a database with 2 fields, the query works fine, but when there are more fields, it doesn't work.

I have the same code for both, and I can not find the problem.

using System.Data.OleDb; // By using this namespace I can connect to the Access Database. namespace WindowsFormsApplication1 { public partial class Form1 : Form { private OleDbConnection myconn; public Form1() { InitializeComponent(); myconn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Users\leelakrishnan\Desktop\NewManageContacts.mdb"); } private void Form1_Load(object sender, EventArgs e) { // TODO: This line of code loads data into the 'newManageContactsDataSet.Contacts' table. You can move, or remove it, as needed. // this.contactsTableAdapter.Fill(this.newManageContactsDataSet.Contacts); // TODO: This line of code loads data into the 'newManageContactsDataSet.Contacts' table. You can move, or remove it, as needed. this.contactsTableAdapter.Fill(this.newManageContactsDataSet.Contacts); } private void button1_Click(object sender, EventArgs e) { OleDbCommand cmd = new OleDbCommand(); cmd.CommandType = CommandType.Text; // string query = "insert into Contacts (fname,lname,llnum,mobnum,e-mail,street,city,country) values ('" + textBox1.Text + "','" + textBox2.Text + "','" + textBox3.Text + "','" + textBox4.Text + "','" + textBox5.Text + "','" + textBox6.Text + "','" + textBox7.Text + "','" + textBox8.Text + "')"; cmd.CommandText = @"insert into Contacts (fname,lname,llnum,mobnum,e-mail,street,city,country) values ('" + textBox1.Text + "','" + textBox2.Text + "','" + textBox3.Text + "','" + textBox4.Text + "','" + textBox5.Text + "','" + textBox6.Text + "','" + textBox7.Text + "','" + textBox8.Text + "')"; cmd.Connection = myconn; myconn.Open(); cmd.ExecuteNonQuery(); System.Windows.Forms.MessageBox.Show("User Account Succefully Created", "Caption", MessageBoxButtons.OKCancel, MessageBoxIcon.Information); myconn.Close(); } private void button2_Click(object sender, EventArgs e) { textBox1.Text = ""; textBox2.Text = ""; textBox3.Text = ""; textBox4.Text = ""; textBox5.Text = ""; textBox6.Text = ""; textBox7.Text = ""; textBox8.Text = ""; } private void textBox1_TextChanged(object sender, EventArgs e) { } } } 

This is the code for a table with two fields

 public partial class Form1 : Form { private OleDbConnection myCon; public Form1() { InitializeComponent(); myCon = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Users\leelakrishnan\Desktop\Database1.mdb"); } private void Form1_Load(object sender, EventArgs e) { // TODO: This line of code loads data into the 'database1DataSet.Table1' table. You can move, or remove it, as needed. this.table1TableAdapter.Fill(this.database1DataSet.Table1); } private void button1_Click(object sender, EventArgs e) { OleDbCommand cmd = new OleDbCommand(); cmd.CommandType = CommandType.Text; cmd.CommandText = "insert into Table1 (name,fname) values ('" + textBox1.Text + "','" + textBox2.Text + "')"; cmd.Connection = myCon; myCon.Open(); cmd.ExecuteNonQuery(); System.Windows.Forms.MessageBox.Show("User Account Succefully Created", "Caption", MessageBoxButtons.OKCancel, MessageBoxIcon.Information); myCon.Close(); } private void button2_Click(object sender, EventArgs e) { textBox1.Text = ""; textBox2.Text = ""; } } 

Answer 1

Additional fields that you are trying to insert may have values ​​that cannot be combined into a valid SQL statement. For instance:

 string field1 = "meh"; string field2 = "whatever"; string field3 = "'Ahoy!' bellowed the sailor."; var cmd = new SqlCommand( "INSERT INTO blah (x, y, z) VALUES ('" + field1 + "', '" + field2 + "', '" + field3 + '")"); 

Imagine what concatenated SQL would look like, given the above input.

Worse, imagine the SQL that you will execute if someone enters this into your form:

 field3 = "Bobby'); DROP TABLE Users; -- "; 

Use parameterized queries via cmd.Parameters.Add or AddRange (described here ). The above example can be fixed in this way:

 var cmd = new SqlCommand("INSERT INTO blah (x, y, z) VALUES (@x, @y, @z)"); cmd.Parameters.AddRange(new[] { new SqlParameter("@x", field1), new SqlParameter("@y", field2), new SqlParameter("@z", field2) }); 

Answer 2

If you work with Databases , then basically use the help of the try-catch block operator, which will help you and help you with your code. Here I show you how to insert some values ​​into the database using the Click Button event.

  private void button2_Click(object sender, EventArgs e) { System.Data.OleDb.OleDbConnection conn = new System.Data.OleDb.OleDbConnection(); conn.ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;" + @"Data source= C:\Users\pir fahim shah\Documents\TravelAgency.accdb"; try { conn.Open(); String ticketno=textBox1.Text.ToString(); String Purchaseprice=textBox2.Text.ToString(); String sellprice=textBox3.Text.ToString(); String my_querry = "INSERT INTO Table1(TicketNo,Sellprice,Purchaseprice)VALUES('"+ticketno+"','"+sellprice+"','"+Purchaseprice+"')"; OleDbCommand cmd = new OleDbCommand(my_querry, conn); cmd.ExecuteNonQuery(); MessageBox.Show("Data saved successfuly...!"); } catch (Exception ex) { MessageBox.Show("Failed due to"+ex.Message); } finally { conn.Close(); } 

Answer 3

 private void btnSave_Click(object sender, EventArgs e)** { OleDbCommand cmd = new OleDbCommand(); cmd.CommandType = CommandType.Text; cmd.CommandText = @"insert into Personal (P_name, P_add,P_Phone)VALUES('" + txtName.Text + "','" +txtAddress.Text + "','" + txtPhone.Text + "')"; cmd.Connection = con; con.Open(); cmd.ExecuteNonQuery(); System.Windows.Forms.MessageBox.Show("Recrod Succefully Created"); con.Close(); txtName.Text = ""; txtAddress.Text = ""; txtPhone.Text = ""; } 

Answer 4

this code to the public:

  OleDbConnection con = new OleDbConnection(@"Provider = Microsoft.Jet.OLEDB.4.0; Data Source = C:\Users\Mohammadhoseyn_mehri\Documents\Data.mdb"); 

this code for the shift button:

  try { craeteaccount(); else { MessageBox.Show("Please re Enter Your PassWord"); } } catch(Exception ex) { MessageBox.Show(ex.Message); } finally { MessageBox.Show("Data saved successfuly...!"); con.Close(); } 

this code to create an account method:

 OleDbDataAdapter adapter = new OleDbDataAdapter("SELECT * from Login", con); con.Open(); String ticketno = textBox2.Text.ToString(); String Purchaseprice = textBox1.Text.ToString(); String my_querry = $"INSERT INTO Login(username,pass)VALUES('{ticketno}','{Purchaseprice}')"; OleDbCommand cmd = new OleDbCommand(my_querry, con); cmd.ExecuteNonQuery();