using (var file = File.Create("pricequote.txt"))
{
    ...........                        
}

using (var file = File.OpenRead("pricequote.txt"))
{
    ..........
}

简单，容易，也处置/清理对象一旦你完成它。

使用文件。ReadAllText和File.WriteAllText。

MSDN示例节选:

// Create a file to write to.
string createText = "Hello and Welcome" + Environment.NewLine;
File.WriteAllText(path, createText);

...

// Open the file to read from.
string readText = File.ReadAllText(path);

简单:

String inputText = "Hello World!";

File.WriteAllText("yourfile.ext",inputText); //writing

var outputText = File.ReadAllText("yourfile.ext"); //reading

您正在寻找File、StreamWriter和StreamReader类。

     class Program
    { 
         public static void Main()
        { 
            //To write in a txt file
             File.WriteAllText("C:\\Users\\HP\\Desktop\\c#file.txt", "Hello and Welcome");

           //To Read from a txt file & print on console
             string  copyTxt = File.ReadAllText("C:\\Users\\HP\\Desktop\\c#file.txt");
             Console.Out.WriteLine("{0}",copyTxt);
        }      
    }

或者，如果你真的很注重线条:

System.IO.File也包含一个静态方法WriteAllLines，所以你可以这样做:

IList<string> myLines = new List<string>()
{
    "line1",
    "line2",
    "line3",
};

File.WriteAllLines("./foo", myLines);