Escape sequences and escape characters
From CodeCodex
Escape characters (also called escape sequences or escape codes) are used to signal an alternative interpretation of a series of characters. Most commonly, escape characters are used to solve the problem of using special characters inside a string declaration.
For example, if you wanted String A to have the value:
The question is, "to be or not to be"
You would need to use an escape character to keep the compiler from interpreting the " character as the end of the string:
String A = "The question is \"to be or not to be\""
Contents |
[edit] Implementations
[edit] VB
Visual Basic (VB) escape characters:
| For this | Use this | Setting x to: | Printing x will yield: |
|---|---|---|---|
| " | "" or Chr(34) | "He said ""hi"""
"He said " & Chr(34) & "hi" & Chr(34) | He said "hi" |
| [enter] | vbCrLf | "He said " & vbCrLf & "he would" | He said he would |
[edit] C / C++
C and C++ escape characters:
| For this | Use this | Setting x to: | Printing x will yield: |
|---|---|---|---|
| ' | \' | "Don\'t do that" | Don't do that |
| " | \" | "She said \"hi\"" | She said "hi" |
| \ | \\ | "Backslash: \\" | Backslash: \ |
| [newline] | \n | "1\n2" | 1 2 |
| [horizontal tab] | \t | "1\t2" | 1 2 |
| [backspace] | \b | "12\b3" | 13 |
| [16 bit unicode] | \uxxxx | "Katakana a: \u30A1" | Katakana a: ァ |
| [32 bit unicode] | \Uxxxxxxxx | "Katakana a: \U000030A1" | Katakana a: ァ |
| [numeric escape sequence.] | \xnn | "Printing the ESC character: \x1Bzyxwu" | "Printing the ESC character: yxwu" |
[edit] Delphi
Delphi escape characters:
| For this | Use this | Setting x to: | Printing x will yield: |
|---|---|---|---|
| ' | '' | 'Don''t do that'
Remark: This is not a double quote, but two single quotes! | Don't do that |
| [16 or 32-bit Unicode] | #d or #$x | 'First Line'#13#10'Second Line' | First Line Second Line |
[edit] Java
Java escape characters:
[edit] Single Characters
| For this | Use this | Setting x to: | Printing x will yield: |
|---|---|---|---|
| ' | \' | "Don\'t do that" | Don't do that |
| " | \" | "She said \"hi\"" | She said "hi" |
| \ | \\ | "Backslash: \\" | Backslash: \ |
| [newline] | \n | "1\n2" | 1 2 |
| [horizontal tab] | \t | "1\t2" | 1 2 |
| [backspace] | \b | "12\b3" | 13 |
| [16 bit unicode] | \uxxxx | "Katakana a: \u30A1" | Katakana a: ァ |
| [32 bit unicode] | \Uxxxxxxxx | "Katakana a: \u000030A1" | Katakana a: ァ |
[edit] Unicode
Unicode escape characters:
| For this | Use this | Setting x to: | Printing x will yield: |
|---|---|---|---|
| ' | \u0027 | "Don\u0027t do that" | Don't do that |
| " | \u0022 | "She said \u0022hi\u0022" | She said "hi" |
| \ | \u0008 | "Backslash: \u0008" | Backslash: \ |
| [newline] | \u000a | "1\u000a2" | 1 2 |
| [horizontal tab] | \u0009 | "1\u00092" | 1 2 |
| [backspace] | \u0008 | "12\u00083" | 13 |
[edit] PHP
PHP escape characters:
[edit] Single quoted strings
| For this | Use this | Setting x to: | Printing x will yield: |
|---|---|---|---|
| ' | \' | 'Don\'t do that' | Don't do that |
| \ | \\ | 'This is a backslash: \\'
Remark: Only necessary before a single quote or at the end of a string. | This is a backslash: \ |
[edit] Double quoted strings
| For this | Use this | Setting x to: | Printing x will yield: |
|---|---|---|---|
| " | \" | "She said \"hi\"" | She said "hi" |
| \ | \\ | "Backslash: \\" | Backslash: \ |
| $ | \$ | "100\$" | 100$ |
| [newline, LF, 0x0A] | \n | "1\n2" | 1 2 |
| [carriage return, CR, 0x0D] | \r | "1\r2" | 2 |
| [horizontal tab] | \t | "1\t2" | 1 2 |
[edit] Python
Python escape characters:
| For this | Use this | Setting x to: | Printing x will yield: |
|---|---|---|---|
| ' | \' | "Don\'t do that" | Don't do that |
| " | \" | "She said \"hi\"" | She said "hi" |
| \ | \\ | "Backslash: \\" | Backslash: \ |
| [newline] | \n | "1\n2" | 1 2 |
| [horizontal tab] | \t | "1\t2" | 1 2 |
| [backspace] | \b | "12\b3" | 13 |
| [16 bit unicode] | \uxxxx | "Katakana a: \u30A1" | Katakana a: ァ |
| [32 bit unicode] | \Uxxxxxxxx | "Katakana a: \u000030A1" | Katakana a: ァ |
[edit] XML
XML escape characters:
| For this | Use this | Setting an element to: | will yield: |
|---|---|---|---|
| ' | ' | Don't do that | Don't do that |
| " | " | She said "hi" | She said "hi" |
| & | & | H&M | H&M |
| < | < | a d is a < | a d is a < |
| > | > | 5>6 | 5>6 |
| Unicode (hex) | &#xXXX; | a d is a d | a d is a d |
| Unicode (dec) | { | sleeps like Z | sleeps like Z |
[edit] SQL
| For this | Use this | Setting x to: | Printing x will yield: |
|---|---|---|---|
| ' | \' | "Don\'t do that" | Don't do that |
| " | \" | "She said \"hi\"" | She said "hi" |
| \ | \\ | "Backslash: \\" | Backslash: \ |
| [newline] | \n | "1\n2" | 1 2 |
[edit] URL
URL escape characters:
| For this | Use this | Setting x to: | Printing x will yield: |
|---|---|---|---|
| Space | %20 | help%20me | help me |
| % | %25 | 100%25%20pure | 100% pure |
| < | %3C | x%3Cy | x<y |
| > | %3E | x%3Ey | x>y |
| Ascii-Code | %xx |
