追加在C＃中的文本文件

Question

我想写从C＃一个txt文件，如下所示：

File.WriteAllText("important.txt", Convert.ToString(c)); 
File.WriteAllLines("important.txt", (from r in rec 
        select r.name + " " + r.num1 + " " + r.num2 + " " + r.mult + " " + r.rel).ToArray()); 

但第二File.WriteAllLines覆盖该文件中的第一项。任何建议如何追加数据？

Answer 1

试试这个

File.WriteAllLines("important.txt", Convert.ToString(c) + (from r in rec 
        select r.name + " " + r.num1 + " " + r.num2 + " " + r.mult + " " + r.rel).ToArray()); 

Answer 2

你应该使用File.AppendAllLines，所以像：

File.WriteAllText("important.txt", Convert.ToString(c)); 
File.AppendAllLines("important.txt", (from r in rec 
        select r.name + " " + r.num1 + " " + r.num2 + " " + r.mult + " " + r.rel).ToArray()); 

System.IO.File.AppendAllLines从.NET Framework 4.0中存在。如果您使用.NET Framework 3.5，则有AppenAllText方法，您可以这样编写代码：

File.WriteAllText("important.txt", Convert.ToString(c)); 
File.AppendAllText("important.txt", string.Join(Environment.NewLine, (from r in rec 
         select r.name + " " + r.num1 + " " + r.num2 + " " + r.mult + " " + r.rel).ToArray()));