C＃异常和forloop中的数字 [英] C# Exceptions and number in forloop

问题描述

我显示两个例外情况b
第一个是当我没有把数字放在k中时b $


第二个例外如果K比蛋更多，那么我在Parameters.AddWithValue中得到一个例外。


我想添加一个MessageBox.Show让它添加正确的数字给k





你还将如何添加每行的输出数字。



1     EG216455

2     nEG216456

3     nEG216457

4     nEG216458

6     nEG216459

7     nEG216460

I show two Exceptions
The first one is when I do not put a number in k

The second Exceptions is if K is more then egg I get an exception in the Parameters.AddWithValue

I like to add a MessageBox.Show to have it add the correct number to k


also how would you add to the output numbers for each row.

1     EG216455
2     nEG216456
3     nEG216457
4     nEG216458
6     nEG216459
7     nEG216460

private void button1_Click(object sender, EventArgs e)
        {
            string egg = textBox1.Text; //egg will show "EG216455\r\nEG216456\r\nEG216457\r\nEG216458\r\nEG216459\r\nEG216460"	
            int k = Convert.ToInt32(textBox2.Text);  // did not put anything in k --- System.FormatException: 'Input string was not in a correct format.'
            string[] stringSeparators = new string[];//EG216455\r\nEG216456\r\nEG216457\r\nEG216458\r\nEG216459\r\nEG216460
            string[] s = egg.Split(stringSeparators, StringSplitOptions.None);


            DataTable dtSerial = new DataTable();
            DataTable table = new DataTable();

            for (int i = 0; i < k; i++)
            {
                                   //ConfigurationManager.ConnectionStrings["pie"].ConnectionString;
                string connString = @"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=Database.mdf;Integrated Security=True";

                using (SqlConnection con = new SqlConnection(connString))
                {
                    using (var cmd = new SqlCommand("SELECT ItemCode,ItemName FROM Table1  where ItemCode = @egg", con))//select eggcounter From [Product].[Counter01unit]  where eggcounter = @egg
                    {
                        cmd.Parameters.AddWithValue("@egg", s[i]); //Exception Unhandled -- System.IndexOutOfRangeException: 'Index was outside the bounds of the array.'
                        con.Open();
                        SqlDataReader reader = cmd.ExecuteReader();
                        dtSerial.Load(reader);
                        table = dtSerial.Clone();
                        foreach (DataRow dr in dtSerial.Rows)
                        {

                            table.Rows.Add(dr.ItemArray);
                        }
                    }
                    con.Close();
                }
            }


            dataGridView1.DataSource = dtSerial;
        }

推荐答案

我显示两个异常

第一个是当我没有在k中放一个数字时$ b

我想添加一个MessageBox.Show让它添加正确的数字到k $

I show two Exceptions
The first one is when I do not put a number in k

I like to add a MessageBox.Show to have it add the correct number to k

private void button1_Click(object sender, EventArgs e)
        {
            string egg = textBox1.Text; //egg will show "EG216455\r\nEG216456\r\nEG216457\r\nEG216458\r\nEG216459\r\nEG216460"	
            int k = Convert.ToInt32(textBox2.Text);  // did not put anything in k --- System.FormatException: 'Input string was not in a correct format.'

int k;
bool res = Int32.TryParse(textBox2.Text, out k);
if(!res) // TryParse returned false ...
{
    // pop up a message box requesting a valid number, etc.
    // ...
    return; // leave button click event handler
}

- Wayne

- Wayne

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