C # Beginners-Text Replacement tool command line version

Beginners | command line The program uses regular expressions for text substitution, breadth-first traversal subdirectory (basic knowledge is important), resolving the problem of unable to replace the carriage return line
Class Replacee
{

<summary>
Replacing characters in a file
</summary>
<param name= "Filefullname" > File Full name </param>
<param name= "Replacedby" > string used for substitution </param>
<param name= "FindPattern" > string used for lookup </param>
<param name= "Isbackup" > whether to back up files </param>
private static void Doreplace (String filefullname, String Replacedby, String findpattern, bool isbackup)
{
string result = String. Empty;
String inputtext = String. Empty;
string replacement = Replacedby;
string Pat = FindPattern;
Regex r = new Regex (PAT, regexoptions.ignorecase);

Try
{
using (StreamReader sr = new StreamReader (filefullname))
{
Inputtext = Sr. ReadToEnd ();
}

Compile the regular expression.
if (R.ismatch (Inputtext))
{
if (Isbackup = = True)
{
Try
{
File.Copy (Filefullname, Filefullname + ". bak");
}
catch (System.IO.IOException ex)
{
File.Copy (Filefullname, Filefullname + ". Bak", true);
Console.WriteLine (ex. message);
}
}
result = R.replace (inputtext, replacement);

Add some text to the file.
using (StreamWriter sw = new StreamWriter (filefullname))
{
Sw. Write (result);
}
}
Console.WriteLine (Filefullname);
}
catch (Exception e)
{

Console.WriteLine ("The process failed: {0}", e.tostring ());
Throw (e);
}
}

<summary>
Traverse Directory
</summary>
<param name= "path" > Start path </param>
<param name= "Replacedby" > string used for substitution </param>
<param name= "FindPattern" > string used for lookup </param>
<param name= "Isbackup" > whether to back up files </param>
<param name= "Isgetsubfloder" > whether to get subfolders </param>
public static void Travelreplace (string path, String replacedstr, String findpattern, bool isbackup, BOOL Isgetsubfloder)
{
Queue queue = new Queue ();
DirectoryInfo di = null;
String subpath = String. Empty;
String Currentpath = String. Empty;
filesysteminfo[] dirs = null;

Queue. Enqueue (path);
while (queue. Count > 0)
{
Currentpath = (string) queue. Dequeue ();
DI = new DirectoryInfo (Currentpath);

Get files under current Directiory
filesysteminfo[] files = di. GetFiles ("*.sql");
foreach (FileSystemInfo f in Files)
{
Doreplace (F.fullname, Replacedstr, FindPattern, isbackup);
}

Get only subdirectories
if (Isgetsubfloder = = True)
{
dirs = di. GetDirectories ();
foreach (FileSystemInfo d in dirs)
{
Subpath = D.fullname;
Queue. Enqueue (subpath);
Console.WriteLine (subpath);
}
}
}
}
}

Test:
Replacee.travelreplace (@ "E:\temp\ttt", "\ r \ n);", @ "(\ r \ n) {2,}\);", true, true;