数据的导入导出问题。 - 黑马程序员技术交流社区

if(ofdImport.ShowDialog()!=DialogResult.OK)
{
MessageBox.Show("导入失败");
}
string dataDir = AppDomain.CurrentDomain.BaseDirectory;
if (dataDir.EndsWith(@"\bin\Debug\")
|| dataDir.EndsWith(@"\bin\Release\"))
{
dataDir = System.IO.Directory.GetParent(dataDir).Parent.Parent.FullName;
AppDomain.CurrentDomain.SetData("DataDirectory", dataDir);
}
using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=E:\我的第一个mdf解决\数据导入导出\Database4.mdf;Integrated Security=True;User Instance=True"))
{
conn.Open();
using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=E:\我的第一个mdf解决\数据导入导出\Database4.mdf;Integrated Security=True;User Instance=True"))
{
conn.Open();
using (SqlCommand cmd = conn.CreateCommand())
{
cmd.CommandText = "insert into T_Persons values(@name,@age)";
using (FileStream filestream = File.OpenRead(ofdImport.FileName)) //打开这个文件
{
using (StreamReader streamreader = new StreamReader(filestream)) //读取导入的这个文件
{
string line = null;
while ((line = streamreader.ReadLine()) != null)
{
string[] remove = line.Split('|');
string name = remove[0];
int age = Convert.ToInt32(remove[1]);
cmd.Parameters.Clear();
cmd.Parameters.Add(new SqlParameter("name", name));
cmd.Parameters.Add(new SqlParameter("@age", age));
cmd.ExecuteNonQuery();
}
}
}
}
}

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if (ofdOutput.ShowDialog() != DialogResult.OK)
{
MessageBox.Show("导出失败");
}
string dataDir = AppDomain.CurrentDomain.BaseDirectory;
if (dataDir.EndsWith(@"\bin\Debug\")
|| dataDir.EndsWith(@"\bin\Release\"))
{
dataDir = System.IO.Directory.GetParent(dataDir).Parent.Parent.FullName;
AppDomain.CurrentDomain.SetData("DataDirectory", dataDir);
}
using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=E:\我的第一个mdf解决\数据导出\Database6.mdf;Integrated Security=True;User Instance=True"))
{
conn.Open();
using (SqlCommand cmd = conn.CreateCommand())
{
cmd.CommandText = "select * from T_Persons";
using (SqlDataReader reader = cmd.ExecuteReader())
{
using (FileStream filestream = new FileStream(ofdOutput.FileName, FileMode.Append, FileAccess.Write))
{
StreamWriter sw = new StreamWriter(filestream);
whlile (reader.Read()) //逐行读取每一个信息，比如第一行
{
string name = reader.GetString(reader.GetOrdinal("Name")); //比如读取第一行中Name那里列中的内容
string age = reader.GetString(reader.GetOrdinal("Age")); /比如读取第一行中Age那里列中的内容
string line = name + "|" + age;
sw.WriteLine(line);
}
sw.Flush();
}
}
MessageBox.Show("导出成功");
}

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using (SqlConnection conn = new SqlConnection(@"Data Source = .; Initial Catalog = DataBase1; User ID = sa; Pwd = 1234;"))
{
conn.Open();
using (SqlCommand comm = conn.CreateCommand())
{
comm.CommandText = "select Name,Age from T_Persons ";
using (SqlDataReader reader = comm.ExecuteReader())
{
using (FileStream fileStream = new FileStream(sfdExport.FileName,FileMode.Append,FileAccess.Write))
{
using (StreamWriter streamWriter = new StreamWriter(fileStream))
{
while (reader.Read())
{
//string name = reader["Name"].ToString();
//string age = reader["age"].ToString();
//string str = string.Join("|", new string[] { name, age });
string name = reader.GetString(reader.GetOrdinal("Name"));
//不能用这种方法获取Age的值，因为它是Int32类型的
//string age = reader.GetString(reader.GetOrdinal("age"));
int age = reader.GetInt32(reader.GetOrdinal("age"));
string str = name + "|" + age;
streamWriter.WriteLine(str);
}
streamWriter.Flush();
}
}
}
}
}

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