要检查，如果条件是否存在于数据表或记录不

Question

SqlCommand cmd1 = new SqlCommand("select * from app where date='" + dateTimePicker2.Value + "'", connection); 
    // MessageBox.Show(cmd1.CommandText); 
    SqlDataAdapter da = new SqlDataAdapter(cmd1); 
    DataTable dt = new DataTable(); 

    da.Fill(dt); 
    //dataGridView1.DataSource = dt; 
    connection.Open(); 
    if (dt.) 
    { 
     textBox1.Text = dt.Rows[0]["company"].ToString(); 
     textBox2.Text = dt.Rows[0]["place"].ToString(); 
     dateTimePicker1.Text = dt.Rows[0]["date"].ToString(); 
     textBox3.Text = dt.Rows[0]["time"].ToString(); 
    } 
    else 
    { 

    } 
    connection.Close(); 
    control_logoff(); 
    adminlogin(); 
    } 

在我的应用我要检查，如果数据表中没有记录它不应该抛出错误，如没有一行位置0

Answer 1

如何

if(dt.Rows.Count() != 0){} 

Answer 2

if(dt.Rows.Count > 0) should do it.