Create File If File Does Not Exist

Question

I need to get my code to read if file doesnt exist create else append. Right now it is reading if it does exist create and append. Here is the code:

if (File.Exists(path)) {     using (StreamWriter sw = File.CreateText(path))     { 

Would I do this?

if (! File.Exists(path)) {     using (StreamWriter sw = File.CreateText(path))     { 

Edit:

string path = txtFilePath.Text;  if (!File.Exists(path)) {     using (StreamWriter sw = File.CreateText(path))     {         foreach (var line in employeeList.Items)         {             sw.WriteLine(((Employee)line).FirstName);             sw.WriteLine(((Employee)line).LastName);             sw.WriteLine(((Employee)line).JobTitle);         }     } } else {     StreamWriter sw = File.AppendText(path);      foreach (var line in employeeList.Items)     {         sw.WriteLine(((Employee)line).FirstName);         sw.WriteLine(((Employee)line).LastName);         sw.WriteLine(((Employee)line).JobTitle);     }     sw.Close(); } 

}

Answer 1

You can simply call

using (StreamWriter w = File.AppendText("log.txt")) 

It will create the file if it doesn't exist and open the file for appending.

Edit:

This is sufficient:

string path = txtFilePath.Text;                using(StreamWriter sw = File.AppendText(path)) {   foreach (var line in employeeList.Items)                    {                         Employee e = (Employee)line; // unbox once     sw.WriteLine(e.FirstName);                          sw.WriteLine(e.LastName);                          sw.WriteLine(e.JobTitle);    }                 }      

But if you insist on checking first, you can do something like this, but I don't see the point.

string path = txtFilePath.Text;                  using (StreamWriter sw = (File.Exists(path)) ? File.AppendText(path) : File.CreateText(path))                  {                           foreach (var line in employeeList.Items)                          {                                sw.WriteLine(((Employee)line).FirstName);                                sw.WriteLine(((Employee)line).LastName);                                sw.WriteLine(((Employee)line).JobTitle);                          }                   }  

Also, one thing to point out with your code is that you're doing a lot of unnecessary unboxing. If you have to use a plain (non-generic) collection like ArrayList, then unbox the object once and use the reference.

However, I perfer to use List<> for my collections:

public class EmployeeList : List<Employee> 

Answer 2

or:

using FileStream fileStream = File.Open(path, FileMode.Append); using StreamWriter file = new StreamWriter(fileStream); // ...