Question

Using hostfile in C# I can block websites but I couldn’t unblock them.

String path = @"C:\Windows\System32\drivers\etc\hosts";
StreamWriter sw = new StreamWriter(path, true);
sitetoblock = "\r\n127.0.0.1\t" + txtException.Text;
sw.Write(sitetoblock);
sw.Close();

MessageBox.Show(txtException.Text + " is blocked", "BLOCKED");
lbWebsites.Items.Add(txtException.Text);
txtException.Clear();

Here I need some help to unblock a specific site which is selected from listbox(lbWebsites). Is there a way to remove them from host file? I tried a lot and looked other solutions but something goes wrong in every solution.

Answer 1

You may use a StreamReader to read the hosts file into a string. Then, initialize a new instance of a StreamWriter to write the content gathered back excluding the website you want to unblock.

Example

string websiteToUnblock = "example.com"; //Initialize a new string of name websiteToUnblock as example.com
StreamReader myReader = new StreamReader(@"C:\Windows\System32\drivers\etc\hosts"); //Initialize a new instance of StreamReader of name myReader to read the hosts file
string myString = myReader.ReadToEnd().Replace(websiteToUnblock, ""); //Replace example.com from the content of the hosts file with an empty string
myReader.Close(); //Close the StreamReader

StreamWriter myWriter = new StreamWriter(@"C:\Windows\System32\drivers\etc\hosts"); //Initialize a new instance of StreamWriter to write to the hosts file; append is set to false as we will overwrite the file with myString
myWriter.Write(myString); //Write myString to the file
myWriter.Close(); //Close the StreamWriter

Thanks,

I hope you find this helpful 🙂