c#.net从oracle数据库读取数据后导出的csv文件

protected void down_datacsv(DataTable dt, string filename) {
StringWriter sw = new StringWriter();
string Headsting = "";
//输出表头
foreach (DataColumn col in dtColumns)
{
Headsting += colColumnName + ",";
}
swWriteLine(Headsting);
foreach (DataRow dr in dtRows)
{
swWriteLine(stringJoin(",", drItemArray));

} swClose();
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