private async void btnSignup_Click(object sender, EventArgs e) { if (txtFullname.Text == "") { MessageBox.Show("Full name can not be empty!", "Caro"); } else if (txtUsername.Text == "") { MessageBox.Show("Username can not be empty!", "Caro"); } else if (txtPassword.Text == "") { MessageBox.Show("Password can not be empty!", "Caro"); } else if (txtPassword.Text != password2.Text) { MessageBox.Show("Passwords do not match!", "Caro"); } else if (!reg.IsMatch(textBox1.Text)) { MessageBox.Show("Invalid email format!", "Caro"); } else { bool check = await CaroAPI.SignUp(txtUsername.Text, txtFullname.Text, txtPassword.Text, textBox1.Text); if (check) { MessageBox.Show("Success", "Caro"); } else { MessageBox.Show("Username or Email exists", "Caro"); } } }