C #: Reading CSV file, saving as CSV file

Read CSV file:

In many systems, you need to read the CSV file, I also encountered in a previous project to read the data in the CSV file to the DataTable for processing, the following code

It's a method I wrote about importing data from a CSV file into a DataTable, and now it's posted for you to share:

Getcsvfile ' S FileName and data gets a CSV file and imports the data into the DataTable

MYCSVDT is used to mount the data in a CSV file Datatable,filepath is the path to the CSV file

private bool Opencsvfile (ref DataTable mycsvdt,string filepath)
{
string strpath = filepath; The path of the CSV file
Try
{
int intcolcount = 0;
bool Blnflag = true;

DataColumn MYDC;
DataRow myDR;

String strline;
string [] aryline;
StreamReader MYSR = new StreamReader (Strpath,system.text.encoding.default);

while (strline = MYSR. ReadLine ())!= null)
{
Aryline = strline. Split (New char[]{', '});

Add a column name to a DataTable
if (Blnflag)
{
Blnflag = false;
Intcolcount = Aryline. Length;
int col=0;
for (int i = 0; i < Aryline. Length; i++)
{
col=i+1;
MYDC = new DataColumn (col. ToString ());
Mycsvdt. Columns.Add (MYDC);
}
}

Fill the data and add it to the DataTable
myDR = Mycsvdt. NewRow ();
for (int i = 0; i < Intcolcount; i++)
{
Mydr[i] = Aryline[i];
}
Mycsvdt. Rows.Add (MYDR);
}
return true;

}
catch (Exception e)
{


Throw (Stack.geterrorstack (strpath+) Error reading data in CSV file. "+ E.message, Opencsvfile ("));
return false;
}
}
Save CSV file:

protected void Button1_Click (object sender, EventArgs e)
{
DataTable dt = new DataTable ();
Dt. Columns.Add ("Test1");
Dt. Columns.Add ("Test2");
Dt. Columns.Add ("Test3");
Dt. Columns.Add ("test4");
Dt. Columns.Add ("Test5");
for (int i = 0; i < 6; i++)
{
Dt. Rows.Add ();
Dt. Rows[i][0] = "CN" +i.tostring ();
Dt. ROWS[I][1] = "EN" +i.tostring ();
Dt. ROWS[I][2] = "JN" +i.tostring ();
Dt. ROWS[I][3] = "HK" +i.tostring ();
Dt. ROWS[I][4] = "TW" +i.tostring ();
}

Exportdatagridtocsv (DT);

}

<summary>
Export the data from DataTable to CSV file
</summary>
<param name= "Grid" ></param>
public void Exportdatagridtocsv (DataTable dt)
{
String strfile = "";
String path = "";

File Info Initialization
strfile = "Test";
strfile = strfile + DateTime.Now.ToString ("Yyyymmddhhmmss");
strfile = strfile + ". csv";
Path = Server.MapPath (strfile);



System.IO.FileStream fs = new FileStream (path, System.IO.FileMode.Create, System.IO.FileAccess.Write);
StreamWriter sw = New StreamWriter (FS, New System.Text.UnicodeEncoding ());
Tabel header
for (int i = 0; i < dt. Columns.count; i++)
{
Sw. Write (dt. Columns[i]. ColumnName);
Sw. Write ("T");
}
Sw. WriteLine ("");
Table body
for (int i = 0; i < dt. Rows.Count; i++)
{
for (int j = 0; j < dt.) Columns.count; J + +)
{
Sw. Write (Delquota (dt. ROWS[I][J]. ToString ()));
Sw. Write ("T");
}
Sw. WriteLine ("");
}
Sw. Flush ();
Sw. Close ();

DownLoadFile (path);
}

private bool DownLoadFile (string _filename)
{
Try
{
System.IO.FileStream fs = System.IO.File.OpenRead (_filename);
byte[] Filedata = new Byte[fs. Length];
Fs. Read (filedata, 0, (int) fs. Length);
Response.Clear ();
Response.AddHeader ("Content-type", "Application/notepad");
String FileName = System.Web.HttpUtility.UrlEncode (System.Text.Encoding.UTF8.GetBytes (_filename));
Response.AddHeader ("Content-disposition", "inline;filename=" + System.Convert.ToChar (+) + filename + System.Convert.ToChar (34));
Response.AddHeader ("Content-length", FS. Length.tostring ());
Response.BinaryWrite (Filedata);
Fs. Close ();
System.IO.File.Delete (_filename);
Response.Flush ();
Response.End ();
return true;
}
catch (Exception ex)
{
Ex. Message.tostring ();
return false;
}
}



<summary>
Delete Special Symbol
</summary>
<param name= "str" ></param>
<returns></returns>
public string Delquota (String str)
{
string result = str;
String[] Strquota ={"~", "!", "@", "#", "$", "%", "^", "&", "*", "(", ")", "'", ";", "", ",", ".", "/", ",", " < "," > ","? "};
for (int i = 0; i < strquota.length; i++)
{
if (result. IndexOf (Strquota[i]) >-1)
result = result. Replace (Strquota[i], "");
}
return result;
}