export button now only available if any user is selected

Form1.cs

@@ -48,13 +48,18 @@ 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;
             }
         }
 
         private void dataGrid_CellContentClick(object sender, DataGridViewCellEventArgs e)
         {
+            
+        }
 
+        private System.EventHandler test()
+        {
+            this.exportBtn.Enabled = false;
+            return null;
         }
 
         private void export(string Filter, string FileName)
@@ -120,5 +125,31 @@ namespace it_projekt
         {
 
         }
+        private void DataGridView_CellClick(object sender, DataGridViewCellEventArgs e)
+        {
+            //Check to ensure that the row CheckBox is clicked.
+            if (e.RowIndex >= 0 && e.ColumnIndex == 6)
+            {
+                //Reference the GridView Row.
+                DataGridViewRow row = dataGrid.Rows[e.RowIndex];
+
+                //Set the CheckBox selection.
+                row.Cells[6].Value = Convert.ToBoolean(row.Cells[6].EditedFormattedValue);
+                exportBtn.Enabled = false;
+                //If CheckBox is checked, display Message Box.
+                if (Convert.ToBoolean(row.Cells[6].Value))
+                {
+                    exportBtn.Enabled = true;
+                }
+                foreach (DataGridViewRow r in dataGrid.Rows)
+                {
+                    if (Convert.ToBoolean(r.Cells[6].Value))
+                    {
+                        exportBtn.Enabled = true;
+                    }
+                }
+            }
+        }
+
     }
 }