读与写的问题. - ITeye问答

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读与写的问题.3

写完文件后,接着读文件readLine(),读出来是"".查看了文件内容写进去了,流也关闭了.请问下什么原.

问题补充：using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Data.SqlClient;

namespace ADODataBase
{
    public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }

        private void Form2_Load(object sender, EventArgs e)
        {
            string field = null;
            string value = null;
            string columnCount = null;
            int i = 0;
            int j = 0;
            string pathTwo = @"c:\info\info.txt";
            string[] arrayName=null;
            string[] arrayValue=null;

            FileStream fs = new FileStream(pathTwo, FileMode.Open,FileAccess.Read,FileShare.ReadWrite);
            StreamReader sd = new StreamReader(fs,System.Text.Encoding.GetEncoding("UTF-8"));
            try
            {
                while (sd.Peek()>0)                          {
                    if (i == 0)
                    {
                        columnCount=sd.ReadLine();                                  //得到列的总数.
                        arrayName = new string[int.Parse(columnCount)];            //设定数组的大小.
                        arrayValue = new string[int.Parse(columnCount)];            //设定数组的大小.
                    }
                    else
                    {
                        field = sd.ReadLine().Trim();
                        string[] arr = field.Split(new char[] { '@' });            //写入的数据进行分割.
                        arrayName[j] = arr[0];                                     //把列名放进一个数组.
                        arrayValue[j] = arr[1];                                   //值放进一个数组.
                        j++;
                    }

                    i++;
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
                MessageBox.Show("读数据出现异常");
            }
            finally
            {
                sd.Close();
                fs.Close();
            }
            for(int k=0;k<groupBox1.Controls.Count;k++)               //列名
            {
                Label lb=(Label)groupBox1.Controls[k];
                lb.Text=arrayName[k];
            }
            for(int l=0;l<groupBox2.Controls.Count;l++)             //值
            {
               TextBox tb=(TextBox)groupBox2.Controls[l];
                tb.Text=arrayValue[l];
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {

        }

        private void button4_Click(object sender, EventArgs e)
        {
            string id=textBox7.Text;
            string trueness = textBox8.Text;
            MessageBox.Show("id="+id);
            MessageBox.Show("truenessname="+trueness);
            SqlConnection con=null;
            SqlCommand cmd=null;
            SqlDataReader dr=null;
            try
            {
                con = new SqlConnection("server=localhost;user=sa;pwd=123456;database=usermanage");
                con.Open();
                cmd=new SqlCommand("select * from usertable where id="+int.Parse(id)+"and truenessname='"+trueness+"'",con);
                dr=cmd.ExecuteReader();
                //MessageBox.Show("dr.Read()="+dr.Read());
                if(dr.Read())
                {

                }
                else
                {
                    MessageBox.Show("没有找到此查询条件的结果,请验证后在查询.");
                }

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
                MessageBox.Show("连接失败");
            }
            finally
            {
                dr.Close();
                con.Close();

            }
        }
    }
}

问题补充：第一行不是空字符串,是有字符的,写完之后马上接着读,能读到吗?这程序现在正在写.现在这代码读是换了一个文件路径读的.

问题补充：问题已解决.