写日志 log 到文件夹

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;

namespace DBUtility
{
public class FileHelper
{
public static void writeLog(string strSQL)
{
try
{
string strFileName = DateTime.Now.ToString("yyyy-MM-dd") + ".txt";
string strPath = "d:/log/";
string strAllPath = strPath + strFileName;

if (!Directory.Exists(strPath))
{
Directory.CreateDirectory(strPath);
}

if (File.Exists(strAllPath))
{
StreamWriter sw = new StreamWriter(strAllPath, true);
sw.WriteLine(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + " " + strSQL); // 写入Hello World
sw.Close(); //关闭文件
}
else
{
FileStream fs = new FileStream(strAllPath, FileMode.OpenOrCreate, FileAccess.ReadWrite);
StreamWriter sw = new StreamWriter(fs); // 创建写入流
sw.WriteLine(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + " " + strSQL); // 写入Hello World
sw.Close(); //关闭文件
fs.Close();
}
}
catch (Exception ex) { }
finally { }
}
}
}

2---------------------------

public static void SaveInfoToTxtFile(string info)
{
//如果不存在Log文件夹就创建文件夹
if (Directory.Exists(@"e:iispublishLog") == false)
{
Directory.CreateDirectory(@"e:iispublishLog");
}

string fileName = @"e:iispublishLog" + DateTime.Now.ToString("yyyyMMddHH") + ".txt";

if (!File.Exists(fileName))
{
File.Create(fileName);
}

try
{
using (StreamWriter sWriter = File.AppendText(fileName))
{
sWriter.WriteLine("sdfsdf");
sWriter.Flush();
}
}
catch (Exception err)
{
Console.WriteLine(" 保存控制台显示的信息 出现异常！" + err.Message);
}
finally
{
//如果流不为空，关闭它

}
}