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PHP check whether property exists in object or class
...
property_exists( mixed $class , string $property )
if (property_exists($ob, 'a'))
isset( mixed $var [, mixed $... ] )
if (isset($ob->a))
isset() will return false if property is null
Example 1:
$ob->a = null
var_dump(isset($ob->a)); //...
object==null or null==object?
...e value would be 0 and the article's promise would not hold. The fact that Strings are objects and ints are primitives is irrelevant of the fact that a programmer may forget to init a variable. In this question we simply solve the null String comparison thing.
– cherouvim
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How to trigger Autofill in Google Chrome?
... difficult for webmasters to ensure that Chrome and other form-filling providers can parse their form correctly. Some standards exist; but they put onerous burdens on the implementation of the website, so they’re not used much in practice.
(The "standards" they refer to is a more recent verion o...
Removing input background colour for Chrome autocomplete?
...This works fine, You can change input box styles as well as text styles inside input box :
Here you can use any color e.g. white, #DDD, rgba(102, 163, 177, 0.45).
But transparent won't work here.
/* Change the white to any color ;) */
input:-webkit-autofill,
input:-webkit-autofill:hover,
input:-...
How do you use the ? : (conditional) operator in JavaScript?
...whole left part: 'Hello ' + username, which is always true, because it's a string with a length greater than 0.
– Jeffrey Roosendaal
Aug 15 '19 at 23:00
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How to get POSTed JSON in Flask?
...quotes while JSON strictly requires double quotes for both the key values (strings) as string values. If you want the JSON representation, use json.dumps() with the object.
– Jochem Schulenklopper
Nov 12 '18 at 15:59
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Which cryptographic hash function should I choose?
...challenge-response auth, or for access tokens, or just to index a bunch of strings/files. Performance, on the other hand, is a concern for the OP...
– Seva Alekseyev
May 23 '19 at 17:33
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Where does Git store the SHA1 of the commit for a submodule?
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Yep. I see where it is now. And it matches the id from git submodule status. Thanks.
– Abizern
Feb 17 '11 at 20:21
7
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OpenSSL and error in reading openssl.conf file
...eys
default_md = md5 # message digest algorithm
string_mask = nombstr # permitted characters
distinguished_name = req_distinguished_name
req_extensions = v3_req
[ req_distinguished_name ]
# Variable name Prompt string
#-...
When to use wrapper class and primitive type
...head than their primitive counterparts (memory & boxing).
Another consideration is:
It can be handy to initialize Objects to null or send null parameters into a method/constructor to indicate state or function. This can't be done with primitives.
Many programmers initialize numbers to 0 (defa...