error ช่วยหน่อยคะ...ต้องการตรวจสอบข้อมูลที่รับมาจาก textbox เช็คกับฐานข้อมูลว่าซ้ำหรือไม่

private void check()

{

//int c = ds.Tables["Program"].Rows.Count - 1;

for (int i = 0; i <= da.Tables["Program"].Rows.Count-1 ; i++)

{


if (da.Tables["Program"].Rows[i]["NameProgram"].ToString().Equals(txtNameProgram.Text.Trim()))

{

MessageBox.Show("คุณป้อนข้อมูลซ้ำ !!! กรุณาป้อนข้อมูลใหม่", "ผลการตรวจสอบ", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);

txtID.Text = "";

txtID.Focus();

txtNameProgram.Text = "";

txtNameProcess.Text = "";

}

}

}

private void Add_Click(object sender, EventArgs e)

{

if (txtID.Text.Trim() == "" || txtNameProgram.Text.Trim() == "" || txtNameProcess.Text.Trim() == "")

{

MessageBox.Show("กรุณากรอกข้อมูลให้ครบ !!!!!", "Error", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);

txtID.Text = "";

txtID.Focus();

txtNameProgram.Text = "";

txtNameProcess.Text = "";

return;

}


if (MessageBox.Show("คุณต้องการเพิ่มโปรแกรมใช่หรือไม่?", "คำยืนยัน", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == System.Windows.Forms.DialogResult.Yes)

{

check();

strConn = "Data Source=SKZ-43D05CDB745;Initial Catalog=server1;Integrated Security=True; User ID=sa;Password=1234";

Conn = new SqlConnection();

if (Conn.State == ConnectionState.Open)

{

Conn.Close();

}

Conn.ConnectionString = strConn;

Conn.Open();


StringBuilder sb = new StringBuilder();

SqlTransaction tr = Conn.BeginTransaction();


try

{


sb.Remove(0, sb.Length);

sb.Append("INSERT INTO Program (IDProgram,NameProgram,NameProcess)");

sb.Append("VALUES(@IDProgram,@NameProgram, @NameProcess)");


string sqlAdd;

sqlAdd = sb.ToString();


 

SqlCommand com = new SqlCommand();

com.CommandText = sqlAdd;

com.CommandType = CommandType.Text;

com.Connection = Conn;

com.Transaction = tr;

com.Parameters.Clear();


com.Parameters.Add("@IDProgram", SqlDbType.Int).Value = txtID.Text.Trim(); ;

com.Parameters.Add("@NameProgram", SqlDbType.NVarChar).Value = txtNameProgram.Text.Trim();

com.Parameters.Add("@NameProcess", SqlDbType.NVarChar).Value = txtNameProcess.Text.Trim();

com.ExecuteNonQuery();

tr.Commit();







MessageBox.Show("เพิ่มข้อมูลโปรแกรมเรียบร้อยแล้ว!!!", "ผลการทำงาน", MessageBoxButtons.OK, MessageBoxIcon.Information);

txtID.Text = "";

txtID.Focus();

txtNameProgram.Text = "";

txtNameProcess.Text = "";

ShowData(); 

}

catch (Exception ex)

{

MessageBox.Show("ไม่สามารถเพิ่มข้อมูลโปรแกรมได้ เนื่องจาก " + ex.Message, "ผลการตรวจสอบ", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);

txtID.Text = "";

txtID.Focus();

txtNameProgram.Text = "";

txtNameProcess.Text = "";

}


}

}


private void ShowData() //Refresh Data Gridview and ListDelete Program

{

if (Conn.State == ConnectionState.Open)

{

Conn.Close();

}

Conn.ConnectionString = strConn;

Conn.Open();

string sqldata = " select * from Program ";

SqlDataAdapter da = new SqlDataAdapter(sqldata, Conn);

da.Fill(ds, "Data1");

dgvProgram.ReadOnly = true;

dgvProgram.DataSource = ds.Tables["Data1"];

string sqldata1 = "select NameProgram from Program";

SqlDataAdapter da1 = new SqlDataAdapter(sqldata1, Conn);

da.Fill(ds, "Data2");

checkedListBox.DataSource = ds.Tables["Data2"];

checkedListBox.DisplayMember = "NameProgram";

checkedListBox.ValueMember = "NameProgram";

checkedListBox.SelectedIndex = 0;

}