fixes export being impossible

Database.cs

@@ -9,7 +9,7 @@ namespace it_projekt
     {
         private static Database _database;
         public List<Person> Persons { get; set; }
-        private Database(String username, String password)
+        private Database(string username, string password)
         {
             string connectionString = "server=localhost;port=3306;database=stammdaten;User Id=" + username + ";Password=" + password + ";";
             MySqlConnection connection = new MySqlConnection(connectionString);

Form1.cs

@@ -30,7 +30,6 @@ namespace it_projekt
         private void loginBtn_Click(object sender, EventArgs e)
         {
             LoadUsersFromTable(this.userTxt.Text, this.passTxt.Text);
-
         }
 
 
@@ -47,6 +46,8 @@ namespace it_projekt
                 {
                     this.dataGrid.Rows.Add(person.Id, person.Firstname, person.Lastname, person.department_short, person.department_long, person.CreationDate, false);
                 }
+                this.loginBtn.Enabled = false;
+                this.exportBtn.Enabled = true;
             }
         }