backslash

问题 Can anyone tell me what is happening here? <?php // true var_dump('\\ ' === '\ '); // false var_dump('\\\\ ' === '\\ '); // true var_dump('\\\\ ' === '\\\ '); 回答1: \ inside a string literal introduces several types of escape sequences, \\ is the escape sequence for a literal "\". But, \ s that don't resolve to an escape sequence are also taken as literal "\". Therefor, '\\ ' stands for the string "\ ", '\\\\ ' stands for the string "\\ ", just as '\\\ ' . Try: echo '\\\\ '; -> \\ See http:/

问题 Can anyone tell me what is happening here? <?php // true var_dump('\\ ' === '\ '); // false var_dump('\\\\ ' === '\\ '); // true var_dump('\\\\ ' === '\\\ '); 回答1: \ inside a string literal introduces several types of escape sequences, \\ is the escape sequence for a literal "\". But, \ s that don't resolve to an escape sequence are also taken as literal "\". Therefor, '\\ ' stands for the string "\ ", '\\\\ ' stands for the string "\\ ", just as '\\\ ' . Try: echo '\\\\ '; -> \\ See http:/

问题 How can I escape the backslashes in the string: 'pictures\12761_1.jpg' ? I know about raw string. How can I convert str to raw if I take 'pictures\12761_1.jpg' value from xml file for example? 回答1: You can use the string .replace() method. >>> print r'pictures\12761_1.jpg'.replace("\\", "/") pictures/12761_1.jpg 回答2: You can also use split/join: print "/".join(r'pictures\12761_1.jpg'.split("\\")) EDITED: The other way you may use is to prepare data during it's retrieving(e.g. the idea is to

问题 Just found the following module import in a Python code: from sqlalchemy.ext.declarative import declarative_base,\ AbstractConcreteBase I am curious about the backslash \ at the end of the first line. What's the purpose of it? Wouldn't it be the same as the following? from sqlalchemy.ext.declarative import declarative_base, AbstractConcreteBase 回答1: Yep, it's exactly the same and this is the point of the backslash — it escapes the newline, allowing this long line to be split in two. An

问题 Just found the following module import in a Python code: from sqlalchemy.ext.declarative import declarative_base,\ AbstractConcreteBase I am curious about the backslash \ at the end of the first line. What's the purpose of it? Wouldn't it be the same as the following? from sqlalchemy.ext.declarative import declarative_base, AbstractConcreteBase 回答1: Yep, it's exactly the same and this is the point of the backslash — it escapes the newline, allowing this long line to be split in two. An

问题 Why does it happen that a command line argument passed to a Java class seems to be automagically escaped while in an instantiated String object the escape character () is seemingly ignored. For example, if start with a string like this: SELECT * FROM my_table WHERE my_col like 'ABC_\' ESCAPE '\' And I try running it through a simple class like this: public class EscapeTest { public static void main (String[] args) { String str = "SELECT * FROM my_table WHERE " + "my_col like 'ABC_\' ESCAPE '\

问题 When I do a git status , I see a change list that looks like this: # modified: CustomizablePDFs/InvoiceAdapter.php # deleted: "CustomizablePDFs\\Model/AlignContainer.php" If I add then commit CustomizablePDFs/InvoiceAdapter.php, it will be commited (as it should be) and no longer appear in the status list (good). However, git status will still show deleted: "CustomizablePDFs\\Model/AlignContainer.php" on the status list. If I do a git rm using that file path, it fails saying that the pathspec

问题 // malformed string var str = "C:\Windows\Fonts"; // C:WindowsFonts alert(str.replace(/\\/g, "/")); How do I correctly replace \ with / so I can get C:/Windows/Fonts ? 回答1: Because it is special character use escape mark var str = "C:\\Windows\\Fonts"; 回答2: You need to add one more backslash to show the special character. var str = "C:\\Windows\\Fonts"; alert(str); Whenever you use the special character in JAvascript you need to add one backslash. 来源： https://stackoverflow.com/questions

问题 I need to replace all these tags </script> with these tags </script> Before: -> <script>..code..</script> <script>..code..</script> After: ---> <script>..code..<\/script> <script>..code..<\/script> But this does not work: function myReplace(){ var X = document.getElementById("demo").innerText; var Y = X.replace(/</script>/ig, '<\/script>'); document.getElementById("demo").innerText = Y; } DEMO Here's a related post for a better understanding 回答1: It looks like your expression isn't going to

问题 I use a Mac and I use Shift + Alt + / when I want to type a \ . I'm trying to learn Python and as you can see \ works fine, but not in IDLE. How do I make backslash (\) work in IDLE? 回答1: Since this problem still persists on OSX 10.8 with python 2.7.5 and 3.3.2 and since this is the first google hit when searching for backslash idle here is a more practical solution instead of copy and pasting: Go to: idle->preferences->keys Under Action-Keys replace: expand-word <Option-Key-Slash> with