I use the php the function strpos to find out if a substring is inside a string. But I am confused about an issue.  I have a string with the value "yellow-message"  I used        if (strpos($mm3, "yellow") != false) {         echo "Yes Yellow &lt;br/&gt;";      }   This fails. I get confused. I tried        if (strpos($mm3, "yellow-message") != false) {         echo "Yes Yellow &lt;br/&gt;";      }   This fails. I get more confused. Now I played around with the function, also used offset without any success, finally I get the result that everything work without "y". As example       if (strpos($mm3, "ellow-message") != false) {         echo "Yes Yellow &lt;br/&gt;";      }   Works also        if (strpos($mm3, "-message") != false) {         echo "Yes Yellow &lt;br/&gt;";      }   First I thought the "-" is the problem, but it looks like that the "y" is the problem. Why?
7905
What is the difference between == and ===?  How exactly does the loosely == comparison work? How exactly does the strict === comparison work?  What would be some useful examples?
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That was an interview question that I was unable to answer:  How to check that a string is a palindrome using regular expressions?  p.s. There is already a question "" and it gives a lot of answers in different languages, but no answer that uses regular expressions.
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I'm in the process of moving an application from PHP to Java and there is heavy use of regular expressions in the code.  I've run across something in PHP that doesn't seem to have a java equivalent:  preg_replace_callback()   For every match in the regex, it calls a function that is passed the match text as a parameter.  As an example usage:  $articleText = preg_replace_callback("/\[thumb(\d+)\]/",'thumbReplace', $articleText); # ... function thumbReplace($matches) {    global $photos;    return "&lt;img src=\"thumbs/" . $photos[$matches[1]] . "\"&gt;"; }   What would be the ideal way to do this in Java?
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I have been trying to tokenize a string using SPACE as delimiter but it doesn't work. Does any one have suggestion on why it doesn't work?  Edit: tokenizing using:  strtok(string, " ");   The code is like the following  pch = strtok (str," "); while (pch != NULL) {   printf ("%s\n",pch);   pch = strtok (NULL, " "); }
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How can you check whether a string is convertible to an int?  Let's say we have data like "House", "50", "Dog", "45.99", I want to know whether I should just use the string or use the parsed int value instead.  In JavaScript we had this  function. If the string couldn't be parsed, it would get back NaN.
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I am told that good developers can spot/utilize the difference between Null and False and 0 and all the other good "nothing" entities. What is the difference, specifically in PHP?  Does it have something to do with ===?
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I would like to do the following: $find = &quot;start (.*) end&quot;; $replace = &quot;foo \1 bar&quot;;  $var = &quot;start middle end&quot;; $var =~ s/$find/$replace/;  I would expect $var to contain &quot;foo middle bar&quot;, but it does not work. Neither does: $replace = 'foo \1 bar';  Somehow I am missing something regarding the escaping.
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I am looking for a way to pull the first 100 characters from a string variable to put in another variable for printing.    Is there a function that can do this easily?  For example:  $string1 = "I am looking for a way to pull the first 100 characters from a string variable to put in another variable for printing."; $string2 = 100charfunction($string1); print $string2   To get:  I am looking for a way to pull the first 100 characters from a string vari
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What is the easiest way to highlight the difference between two strings in PHP?  I'm thinking along the lines of the Stack Overflow edit history page, where new text is in green and removed text is in red. If there are any pre-written functions or classes available, that would be ideal.
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Here are the args for my query :  $args = array(     'post_type' =&gt; 'news',     'meta_query' =&gt; array(         array(             'key' =&gt; 'topics',             'value' =&gt; 'sports',         )     ) );   This works when topics is a string, but not when it is an array. I'd like this query to work when topics is for example array( 'sports', 'nonprofit', etc. )  Is there a way to build meta queries with arrays as a meta_key ?
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I'm looking to find records in a table that match a specific number that the user enters.  So, the user may enter 12345, but this could be 123zz4-5 in the database. I imagine something like this would work, if PHP functions worked in MySQL. SELECT * FROM foo WHERE preg_replace(&quot;/[^0-9]/&quot;,&quot;&quot;,bar) = '12345'  What's the equivalent function or way to do this with just MySQL? Speed is not important.
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In Ruby you can easily set a default value for a variable   x ||= "default"   The above statement will set the value of x to "default" if x is nil or false  Is there a similar shortcut in PHP or do I have to use the longer form:  $x = (isset($x))? $x : "default";   Are there any easier ways to handle this in PHP?
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I want to check whether Value1 below contains "abc" within the first X characters. How would you check this with an if statement?  var Value1 = "ddabcgghh";  if (Value1.Contains("abc")) {     found = true; }   It could be within the first 3, 4 or 5 characters.
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What is the difference between == and === in php. I am unsure when to use both.  Updated note: So that it shows up in StackOverflow search, the difference between == and === is the same as the difference between != and !==.
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I often use ($var &amp; 1) in my code, which returns true if $var is an odd number and false if it's an even number.  But what does "&amp;" actually do?
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What would be the best way to look in a string[] to see if it contains a element. This was my first shot at it. But perhaps there is something that I am overlooking. The array size will be no larger than 200 elements.  bool isStringInArray(string[] strArray, string key) {     for (int i = 0; i &lt;= strArray.Length - 1; i++)         if (strArray[i] == key)             return true;     return false; }
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I am not familiar with PHP at all and had a quick question.  I have 2 variables pricePerUnit and InvoicedUnits. Here's the code that is setting these to values:  $InvoicedUnits = ((string) $InvoiceLineItem-&gt;InvoicedUnits); $pricePerUnit = ((string) $InvoiceLineItem-&gt;PricePerUnit);   If I output this, I get the correct values. Lets say 5000 invoiced units and 1.00 for price.  Now, I need to show the total amount spent. When I multiply these two together it doesn't work (as expected, these are strings).  But I have no clue how to parse/cast/convert variables in PHP.  What should I do?