I'm currently using iOS UIAutomation and identifying elements with a string generated from an external database that is populated with dynamic data. But iOS uiautomation throws a parser error when the string predicate contains a single quote.
Example:
UIATarget.localTarget().frontMostApp().mainWindow().collectionViews().firstWithPredicate(\"ANY visibleCells.name CONTAINS '" + title + "'")
Note that if title = "Todds Apartment" this locator works fine. But if the string contains a single quote it throws the parser error. So for example if title = "Todd's Apartment" this wouldn't work.
Is there a way for the predicate evaluation within single quotes to contain a single quote?
This is really a question about sanitizing input -- escaping strings for inclusion in a query string of some kind.
You should check out this question on escaping javascript strings for sql. You can probably solve your problem minimally by simply replacing \ with \\ and ' with \' in your input string.
Apple's documentation on predicates didn't seem to offer any information about what characters might need to be escaped.
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Possible Duplicate:
Regular expression to remove HTML tags
Is there an expression which will get the value between two HTML tags?
Given this:
<td class="played">0</td>
I am looking for an expression which will return 0, stripping the <td> tags.
You should not attempt to parse HTML with regex. HTML is not a regular language, so any regex you come up with will likely fail on some esoteric edge case. Please refer to the seminal answer to this question for specifics. While mostly formatted as a joke, it makes a very good point.
The following examples are Java, but the regex will be similar -- if not identical -- for other languages.
String target = someString.replaceAll("<[^>]*>", "");
Assuming your non-html does not contain any < or > and that your input string is correctly structured.
If you know they're a specific tag -- for example you know the text contains only <td> tags, you could do something like this:
String target = someString.replaceAll("(?i)<td[^>]*>", "");
Edit:
Ωmega brought up a good point in a comment on another post that this would result in multiple results all being squished together if there were multiple tags.
For example, if the input string were <td>Something</td><td>Another Thing</td>, then the above would result in SomethingAnother Thing.
In a situation where multiple tags are expected, we could do something like:
String target = someString.replaceAll("(?i)<td[^>]*>", " ").replaceAll("\\s+", " ").trim();
This replaces the HTML with a single space, then collapses whitespace, and then trims any on the ends.
A trivial approach would be to replace
<[^>]*>
with nothing. But depending on how ill-structured your input is that may well fail.
You could do it with jsoup http://jsoup.org/
Whitelist whitelist = Whitelist.none();
String cleanStr = Jsoup.clean(yourText, whitelist);
I have a small issue, so here's a bit of background:
We are developing a Qlik Sense application and we normally write our expressions to an external script. We save these as variables, and then evaluate the variables in the application. The advantage of this is a) we can use better version control with GIT, and b) we can separate the queries from the application if we ever need to change platforms in future.
My Problem:
I have come across a situation where we need to concat a string to the result of an expression, which can be done easily in the application, but when you save the expression to an external file the single quotes around the expression interfere with the single quotes around the string.
I tried
using double quotes for the string only, but qlik doesn't evaluate it correctly.
same goes for the expression using double quotes only.
escaping the single quote inside the expression, eg. "\'" but same story.
What I was thinking of doing next was changing the quote to a rogue character so qlik would ignore it as text, then replacing it with a quote later so qlik would then try to evaluate it.
Example Code:
SET variable = 'if(isnull(month),'Month: ' & date(now(), 'MMM-YYYY'),'Month: ' & only({$<year={2016}, month={6}>}month)';
After some further research I found that Qlik has its own way of escaping characters without using the "\" character. I was able to solve this issue by escaping the inner single quotes like this:
SET variable = 'if(isnull(month),''Month: '' & date(now(), ''MMM-YYYY''),''Month: '' & only({$<year={2016}, month={6}>}month)';
Feels like a pretty silly oversight now, but hopefully this will save someone some time in the future.
I have this string:
201057&channelTitle=null_JS
I want to be able to cut out the '201057' and make it a new variable. But I don't always know how long the digits will be, so can I somehow use the '&' as a reference?\
myDigits substring(0, position of &)?
Thanks
Sure, you can split the string along the &.
String s = "201057&channelTitle=null_JS";
String[] parts = s.split("&");
String newVar = parts[0];
The expected result here is
parts[0] = "201057";
parts[1] = "channelTitle=null_JS";
In production code you chould check of course the length of the parts array, in case no "&" was present.
Several programming languages also support the useful inverse operation
String s2 = parts.join("&"); // should have same value like s
Alas this one is not part of the Java standard libs, but e.g. Apache Commons Lang features it.
Always read the API first. There is an indexOf method in String that will return you the first index of the character/String you gave it.
You can use myDigits.substring(0, myDigits.indexOf('&');
However, if you want to get all of the arguments in the query separately, then you should use mvw's answer.
I'm using the SpanishAnalyzer class in Lucene 3.4. When I want to parse accented words, I'm having a strange result. If I parse, for example, these two words: "comunicación" and "comunicacion", the stems I'm getting are "comun" and "comunicacion". If I instead parse "maratón" and "maraton", I'm getting the same stem for both words ("maraton").
So, at least in my opinion, it's very strange that the same word, "comunicación", gives different results depending on it is accented or not. If I search the word "comunicacion", I should get the same result regardless of whether it's accented or not.
The code I'm using is the next one:
SpanishAnalyzer sa = new SpanishAnalzyer(Version.LUCENE_34);
QueryParser parser = new QueryParser(Version.LUCENE_34, "content", sa);
String str = "comunicación";
String str2 = "comunicacion";
System.out.println("first: " + parser.parse(str)); //stem = comun
System.out.println("second: " + parser.parse(str2)); //stem = comunicacion
The solution I've found to be able to get every single word that shares the stem of "comunicacion", accented or not, is to take off accents in a first step, and then parse it with the Analyzer, but I don't know if it's the right way.
Please, can anyone help me?
Did you check what tokenizer & tokenfilters SpanishAnalyzer uses? There is something called ASCIIFoldingFilter. Try placing it before the StemFilter. It will remove the accents
I am writing a backend application which needs to be able to send multiple SQL commands to a MySQL server.
MySQL >= 5.x support multiple statements, but unfortunately we are interfacing with MySQL 4.x.
I am trying to find a way (hint: regex) to split SQL statements by their semicolon, but it should ignore semicolons in single and double quotes strings.
http://www.dev-explorer.com/articles/multiple-mysql-queries has a very nice regex to do that, but doesn't support double quotes.
I'd be happy to hear your suggestions.
Can't be done with regex, it's insufficiently powerful to parse SQL. There may be an SQL parser available for your language — which is it? — but parsing SQL is quite hard, especially given the range of different syntaxes available. Even in MySQL alone there are many SQL_MODE flags on a server and connection level that can affect how basic strings and comments are parsed, making statements behave quite differently.
The example at dev-explorer goes to amusing lengths to try to cope with escaped apostrophes and trailing strings, but will still fail for many valid combinations of them, not to mention the double quotes, backticks, the various comment syntaxes, or ANSI SQL_MODE.
As bobince said, regular expressions are probably not going to be powerful enough to do this. They're certainly not going to be powerful enough to do it in any halfway elegant manner. The second link cdonner provided also does not address this; most answers there were trying to talk the questioner out of doing this without semicolons; if he had taken the general advice, then he'd have ended up where you are.
I think the quickest path to solving this is going to be with a string scanner function, that examines every character of the string in sequence, and reacts based on a bit of stored state. Rough pseudocode:
Read in a character
If the character is not special, CONTINUE
If the character is escaped (checking this probably requires examining the previous character), CONTINUE
If the character would start a new string or end an existing one, toggle a flag IN_STRING (you might need multiple flags for different string types... I've honestly tried and succeeded at remaining ignorant of the minutiae of SQL quoting/escaping) and CONTINUE
If the character is a semicolon AND we are not currently in a string, we have found a query! OUTPUT it and CONTINUE scanning until the end of the string.
Language parsing is not any of my areas of experience, so you'll want to consider that approach carefully; nonetheless, it's going to be fast (with C-style strings, none of those steps are at all expensive, save possibly for the OUTPUT, depending on what "outputting" means in your context) and I think it should get the job done.
maybe with the following Java Regexp? check the test...
#Test
public void testRegexp() {
String s = //
"SELECT 'hello;world' \n" + //
"FROM DUAL; \n" + //
"\n" + //
"SELECT 'hello;world' \n" + //
"FROM DUAL; \n" + //
"\n";
String regexp = "([^;]*?('.*?')?)*?;\\s*";
assertEquals("<statement><statement>", s.replaceAll(regexp, "<statement>"));
}
I would suggest seeing if you can redefine the problem space so the need to send multiple queries separated only by their terminator is not required.
Try this. Just replaced the 1st ' with \" and it seems to work for both ' and "
;+(?=([^\"|^\\']['|\\'][^'|^\\']['|\\'])[^'|^\\'][^'|^\\']$)