c# - How can I add some values into my database

Question

I'm a beginner in C# and I wrote a code that connect to my database but It give me a error

I did everything from first but nothing happened

private void btnSubmit_Click(object sender, EventArgs e) 
{
     string conString = "data source=DESKTOP-D5VFL9P; initial catalog = university; integrated security = True; MultipleActiveResultSets = True;";

     using (SqlConnection connection = new SqlConnection(conString)) 
     {
         connection.Open();

         using(SqlCommand command = new SqlCommand("INSERT INTO Persons (PersonID, LastName, FirstName, Age, City) VALUES (" + int.Parse(txtPersonID.Text) + ", '" +
    txtLastName.Text + "', '" + txtFirstName.Text + "' ," + int.Parse(txtAge.Text) + ", '" + txtCity.Text + "'", connection)) 
         {
             using(SqlDataReader reader = command.ExecuteReader()) 
             {
                  MessageBox.Show("Data inserted");

                  txtFirstName.Text = "";
                  txtLastName.Text = "";
                  txtPersonID.Text = "";
                  txtAge.Text = "";
                  txtCity.Text = "";
             }
         }
     }
 }

I want to add some values to my database

Answer 1

There should be a ) behind the City. Like txtCity.Text + "')".