C#读写文本文件

static public string Read(string path)
{
StreamReader sr = new StreamReader(path,Encoding.Default);
String line;
StringBuilder sb=new StringBuilder();
while ((line = sr.ReadLine()) != null)
{
sb.AppendLine(line);

}
return sb.ToString();

}

public static string ReadFile(string FilePath)
{
if (System.IO.File.Exists(FilePath))
{
try
{
StreamReader reader = new StreamReader(FilePath, Encoding.GetEncoding("gb2312"));//System.IO.File.OpenText(FilePath);
StringBuilder builder = new StringBuilder();
string str = "";
string str2 = "";
while ((str = reader.ReadLine()) != null)
{
builder.AppendLine(str  );
}
str2 = builder.ToString();
reader.Close();
return str2;
}
catch
{
return "";
}
}
return "";
}

public static bool SaveFile(string FilePath, string type, string content)
{
string path = FilePath;
if (!File.Exists(path))
type = "NEW";
try
{
StreamWriter writer;
if (type == "NEW")
{
using (writer = new StreamWriter(FilePath, false, Encoding.GetEncoding("gb2312")))//System.IO.File.CreateText(path))
{
writer.Write(content);
writer.Flush();
writer.Close();
return true;
}
}
if (type == "ADD")
{
if (System.IO.File.Exists(path))
{
writer = new StreamWriter(path, true, Encoding.GetEncoding("gb2312"));
writer.Write(content);
writer.Flush();
writer.Close();
return true;
}
return false;
}
return false;
}
catch
{
return false;
}
}

 public class FileHelper
    {
        public static string ReadFile(string path)
        {
            StreamReader sr = new StreamReader(path, Encoding.Default);
            String line;
            StringBuilder sb = new StringBuilder();
            while ((line = sr.ReadLine()) != null)
            {
                sb.AppendLine(line);

            }
            return sb.ToString();

        }

        public static IEnumerable<string> ReadFileToEnumerable(string path)
        {
            StreamReader sr = new StreamReader(path, Encoding.Default);
            String line;

            while ((line = sr.ReadLine()) != null)
            {
                yield return line;

            }

        }

        public static IList<T> ReadFileToList<T>(string[] path, Func<string, T> func)
        {
            var list = new List<T>();
            foreach (var item in path)
            {
                list = list.Union(ReadFileToEnumerable(item).Select(func)).ToList();
            }
            return list;
        }
        public static bool AppendFile(string filePath, string type, string content)
        {

            try
            {

                if (System.IO.File.Exists(filePath))
                    {
                        var writer = new StreamWriter(filePath, true, Encoding.GetEncoding("gb2312"));
                        writer.Write(content);
                        writer.Flush();
                        writer.Close();
                        return true;
                    }
                    return false;

            }
            catch
            {
                return false;
            }
        }

        public static bool CreateFile(string filePath, string type, string content)
        {

            try
            {
                StreamWriter writer;

                    using (writer = new StreamWriter(filePath, false, Encoding.GetEncoding("gb2312")))//System.IO.File.CreateText(path))
                    {
                        writer.Write(content);
                        writer.Flush();
                        writer.Close();
                        return true;
                    }

            }
            catch
            {
                return false;
            }
        }

    }