하나 이상의 데이터에 대해 SQL 쿼리를 작성하는 방법은 무엇입니까? 문제가에있다

Question

private void button1_Click(object sender, EventArgs e) 
{ 
     SqlConnection con = new SqlConnection(conString); 
     con.Open(); 

     int tableID; 
     int customerID; 
     customerID = Convert.ToInt32(dataGridView2.SelectedCells[0].Value.ToString()); 
     tableID = Convert.ToInt32(dataGridView1.SelectedCells[0].Value.ToString()); 

     SqlCommand cmd = con.CreateCommand(); 
     cmd.CommandType = CommandType.Text; 
     cmd.CommandText = "select * from Reservationn where TableID='" + tableID+ "CustomerID='"+ customerID +"Capacity='" + textBox2.Text + "Date='"+textBox5.Text+"HourEnd='"+comboBox1.Text+"Reservİnfo='"+textBox6.Text + "'"; 

     cmd.ExecuteNonQuery();   

     DataTable dt = new DataTable(); 
     SqlDataAdapter da = new SqlDataAdapter(cmd); 
     da.Fill(dt); 

     dataGridView3.DataSource = dt;      
     con.Close(); 
} 

: 은

cmd.CommandText = "select * from Reservationn where TableID='" + tableID+ "CustomerID='"+ customerID +"Capacity='" + textBox2.Text + "Date='"+textBox5.Text+"HourEnd='"+comboBox1.Text+"Reservİnfo='"+textBox6.Text + "'"; 

는

는 어떻게이

을 고정 할 수 있습니다 ?

Answer 1

cmd.CommandText = "select * from Reservationn where TableID='" + tableID+ "' and CustomerID='"+ customerID +"' and Capacity='" + textBox2.Text + "' and Date='"+textBox5.Text+"' and HourEnd='"+comboBox1.Text+"' and Reservİnfo='"+textBox6.Text + "'"; 

Answer 2

음은 일회용 객체에 올 때 당신은 using 문을 사용하여 게시 된 쿼리

Answer 3

더 나은 ANDOR 조건 연산자를 누락하고 라훌 말한대로 여러 부울 문을 결합하면서 u는 사용할 필요가 AND OR. 당신이 및 String.format와 쿼리를 작성할 수 있습니다 문자열과 날짜

private void button1_Click(object sender, EventArgs e) 
{ 
    var dt = new DataTable(); 
    var customerID = dataGridView2.SelectedCells[0].Value.ToString(); 
    var tableID = dataGridView1.SelectedCells[0].Value.ToString(); 
    using (var con = new SqlConnection(conString)) 
    { 
     var commandText = string.Format("SELECT * FROM Reservationn WHERE TableID={0} AND CustomerID={1} AND Capacity={2} AND Date='{3}' AND HourEnd='{4}' AND Reservİnfo='{5}'", tableID, customerID, textBox2.Text, textBox5.Text, comboBox1.Text, textBox6.Text); 
     using (var cmd = new SqlCommand(commandText, con)) 
     { 
      con.Open(); 
      var da = new SqlDataAdapter(cmd); 
      da.Fill(dt); 
     } 
    } 
    dataGridView3.DataSource = dt; 
} 

Answer 4

에 대한 작은 따옴표를 잊지 마세요()

는

string query =string.format(“select * from Reservationn where TableID=‘{0}’ and CustomerID=‘{1}’ and Capacity=‘{2}’ and Date=‘{3}’ and HourEnd=‘{4}’ and Reservİnfo=‘{5}’”,tableid,customerid,capacity,date,hourend,reservinfo); cmd.CommandText=query;