这段代码如何提高速度

[weixin_38063369]

await Task.Factory.StartNew(() =>
{

//Parallel.ForEach(list1, (item, loopState) =>
//{
// WriteTextAsync(item, ".\\16进制转换文件\\" + "U-D" + data + ".txt");
//});
//Parallel.ForEach(list2, (item, loopState) =>
//{
// WriteTextAsync(item, ".\\16进制转换文件\\" + "E-W" + data + ".txt");
//});
//Parallel.ForEach(list3, (item, loopState) =>
//{
// WriteTextAsync(item, ".\\16进制转换文件\\" + "N-S" + data + ".txt");
//});
foreach (string c in list1)
{
WriteTextAsync(c, ".\\16进制转换文件\\" + "U-D" + data + ".txt");
}
foreach (string c in list2)
{
WriteTextAsync(c, ".\\16进制转换文件\\" + "E-W" + data + ".txt");
}
foreach (string c in list3)
{
WriteTextAsync(c, ".\\16进制转换文件\\" + "N-S" + data + ".txt");
}
}, TaskCreationOptions.LongRunning);

 public void WriteTextAsync(string text, string path)
        {
            using (StreamWriter outputFile = new StreamWriter(path, true))
            {
                outputFile.WriteLineAsync(text);
            }
        }

please verify my account