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How to convert \\ to \[Answered] RSS

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Last post Jul 02, 2020 03:27 AM by ttprettycoder

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ttprettycode...
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How to convert \\ to \

Jun 29, 2020 07:28 AM|ttprettycoder|LINK
HI experts,

I can't convert '\\' to '\':

I use Replace(),but it not work:
```
"aa\\bb.cc".Replace(@"\\",@"\")
```
like the picture:

https://pasteboard.co/JfirZYv.png

I want to convert 'aa\\bb.cc' to 'aa\bb.cc'
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Mikesdotnett...
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Re: How to convert \\ to \

Jun 29, 2020 07:40 AM|Mikesdotnetting|LINK

Each \ needs escaping in the Replace method:

"aa\\bb.cc".Replace(@"\\\\",@"\\")

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Sean Fang
Contributor

3020 Points

889 Posts
Re: How to convert \\ to \

Jun 29, 2020 10:20 AM|Sean Fang|LINK
Hi ttprettycoder,

Actually, you just create a string with value "aa\\bb.cc" in which the "\" will be escaped. Therefore, you will get "aa\bb.cc". I will show you in below codes.
```
 public static void Main (string[] args) {
    
    string example = "aa\\bb.cc";

    Console.WriteLine(example); // aa\bb.cc
    
    bool containsBackSlash = example.Contains("\\");  //True, contains one back slash
    bool containsDoubleBackSlash = example.Contains(@"\\");  // False, does not contain double back slash

    Console.WriteLine (containsBackSlash);  // True
    Console.WriteLine (containsDoubleBackSlash); // False

    string replacedString1 = example.Replace("\\","++"); // successful, find back slash, produce ++
    string replacedString2 = example.Replace(@"\\","++"); // failed, no double back slash found, nothing changed
    string replacedString3 = example.Replace("\\",@"\"); // actually they are the same, nothing changed


    Console.WriteLine (replacedString1);   // aa++bb.cc
    Console.WriteLine (replacedString2);   // aa\bb.cc
    Console.WriteLine (replacedString3);   // aa\bb.cc
    
  }
```
You could access above codes here: Codes Play Ground

The console result is as below:

The string value contains double back slash but it does not mean that it has two backslashes which are able to be rendered. The first one will be treated as the escape signal.

In your problem, the reason why you can not complete the replacement is that you can not find @"\\" which equals to "\\\\". Therefore, you will see the exactly same string as before.

If you want to make the replacement working, you will have to provide a string @"aa\\bb.cc" or "aa\\\\bb.cc". After that, you will be able to use the method String.Replace(@"\\",@"\") which will change the string @"aa\\bb.cc" to @"aa\bb.cc". You could try these as the previous codes I provided you.

Please bear in mind that each \ will be related to escaping without prefix @.

Hope this can help you.

Best regards,

Sean
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ttprettycode...
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Re: How to convert \\ to \

Jun 29, 2020 11:57 AM|ttprettycoder|LINK

hi, I follow your suggest,but it still not work,like the picture:

https://pasteboard.co/JfkdoAm.png
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mgebhard
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24037 Posts
Re: How to convert \\ to \

Jun 29, 2020 12:20 PM|mgebhard|LINK
ttprettycoder

hi, I follow your suggest,but it still not work,like the picture:

https://pasteboard.co/JfkdoAm.png

The backslash character has special meaning. It is an escape character. The first backslash is a code that changes the behavior of the next character.
```
\' single quote
\" double quote
\\ backslash
\n new line
\r carriage return
\t tab
\b backspace
\f form feed
```
The problem is the code you are showing does not makes sense because there's not a double backslash. There's an escape character and a backslash. Here is an example.
```
var str = "aa\\bb.cc";
console.log(str);
```
Results
```
aa\bb.cc
```
Can you explain the problem you are trying to solve or any error you are receiving?
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ttprettycode...
Member

5 Points

20 Posts

Re: How to convert \\ to \

Jul 02, 2020 03:27 AM|ttprettycoder|LINK

thank you very much.