附加在C＃中的文本文件中

Question

我正在尝试从C＃编写一个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());

但是第二个File.WriteAllLines会覆盖文件中的第一个条目。有任何建议我如何追加数据？

Answer 1

您应该使用File.AppendAllLines，例如：

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存在于.NET framework 4.0中。如果您使用的是.NET Framework 3.5，那么就有AppenAllText方法，您可以像这样编写代码：

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()));

Answer 2

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());