如何在C#中通过选择ComboBox项从MySQL数据库中检索数据值

我正在尝试这种编码&＃xff0c;这个编码中的错误是什么&＃xff1a;

private void comboBox2_SelectedIndexChanged(object sender, EventArgs e)

{

SqlConnection con &＃61; new SqlConnection("Data Source &＃61;TWPL-PC\\SQLEXPRESS;Initial Catalog&＃61;TWPLSOFTWARE;Integrated security &＃61; True");

con.Open();

SqlCommand cmd &＃61; new SqlCommand("select ACC_ID ,ACC_TYPE ,ACC_ADD,ACC_CITY ,ACC_STATE ,ACC_COUNTRY ,ACC_TIN_N0 ,ACC_ECC_NO,ACC_RANGE,ACC_DIVISION ,ACC_COMMISS ,ACC_GST_NO ,ACC_CONTACT_PERSON ,ACC_PHONE_NO ,ACC_MOBILE_NO ,ACC_EMAIL ,ACC_PRICE_CODE ,ACC_APPROVAL_STATUS,ACC_PAN_NO from ACCOUNT where ACC_NAME&＃61;&＃39;" &＃43; comboBox2.SelectedItem.ToString() &＃43; "&＃39;", con);

cmd.Parameters.Add(new SqlParameter("&＃64;ACC_NAME", comboBox2.SelectedItem.ToString()));

SqlDataReader dr &＃61; cmd.ExecuteReader();

while (dr.Read())

{

textBox17.Text &＃61; dr.GetString(0).ToString();

comboBox1.SelectedItem &＃61; dr.GetString(1).ToString();

richTextBox1.Text &＃61; dr.GetString(2).ToString();

textBox2.Text &＃61; dr.GetString(3).ToString();

textBox3.Text &＃61; dr.GetString(4).ToString();

textBox4.Text &＃61; dr.GetString(5).ToString();

textBox9.Text &＃61; dr.GetString(6).ToString();

textBox11.Text &＃61; dr.GetString(7).ToString();

textBox13.Text &＃61; dr.GetString(8).ToString();

textBox14.Text &＃61; dr.GetString(9).ToString();

textBox16.Text &＃61; dr.GetString(10).ToString();

textBox12.Text &＃61; dr.GetString(11).ToString();

textBox5.Text &＃61; dr.GetString(12).ToString();

textBox6.Text &＃61; dr.GetString(13).ToString();

textBox8.Text &＃61; dr.GetString(14).ToString();

textBox7.Text &＃61; dr.GetString(15).ToString();

textBox15.Text &＃61; dr.GetString(16).ToString();

//checkBox1.Checked&＃61;dr.GetString().ToString();

textBox10.Text &＃61; dr.GetString(18).ToString();

}

}

这是我的问题&＃xff1a;

“数据类型text和varchar在等于中是不兼容的

运算符“。