C＃正则表达式转义和替换

Question

I have an API that sends out documents to email. I'm using a paramater that allows me to specify the email message. It requires line breaks to be in Json format (\\n). I'm using Regex to escape the textbox text like shown below.

string JsonMessage = string.Format("{0}\n{1}", System.Text.RegularExpressions.Regex.Escape(this.txtMailMessage.Text), System.Text.RegularExpressions.Regex.Escape(this.txtMailMessage.Text));
        JsonMessage = JsonMessage.Replace("\r", "");
        Console.WriteLine(JsonMessage);

Here is a example output: 5\\r\\n5\\r\\n5

As shown I'm trying to replace the \\r in order to achieve the "line break" in Json. So it would look like this: 5\\n5\\n5

What I can't seem to wrap me head around is that when I cast the JsonMessage = JsonMessage.Replace("\\r", ""); it does not replace the \\r

Answer 1

You need to use JsonMessage.Replace("\\\\r", "");
The \\\\ will be interpreted as a single backslash.

Answer 2

Instead of replacing "\\r" with nothing try and replace "\\r\\n" with "\\n" as

        string mystring = "5\r\n5\r\n5";
        mystring = mystring.Replace("\r\n", "\n");

This will produce "5\\n5\\n5"