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Why is it Valid to Concatenate Null Strings but not to Call “null.ToString()”?
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The first sample will be translated into:
var bob = String.Concat("abc123", null, null, null, "abs123");
The Concat method checks input and translate null as an empty string
The second sample will be translated into:
var wtf = ((object)null).ToString();
So a null reference exception will ...
Best way to test for a variable's existence in PHP; isset() is clearly broken
...f isset().
Since this is takes the array to check as a function argument, PHP will still raise "notices" if the array itself doesn't exist. In some cases, it can validly be argued that each dimension should have been initialised first, so the notice is doing its job. For other cases, a "recursive" ...
How to check if PHP array is associative or sequential?
PHP treats all arrays as associative, so there aren't any built in functions. Can anyone recommend a fairly efficient way to check if an array contains only numeric keys?
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Regular expression to match numbers with or without commas and decimals in text
... are embedded in other text. IMHO anything that fails to pull 1,234.56 and 1234—and only those numbers—out of abc22 1,234.56 9.9.9.9 def 1234 is a wrong answer.
First of all, if you don't need to do this all in one regex, don't. A single regex for two different number formats is hard to maintain...
`static` keyword inside function?
... found some things I hadn't seen before. I did some initial looking in the php manual, but it didn't explain these examples.
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Error message Strict standards: Non-static method should not be called statically in php
I have the following php. However when I see the index.php I get the following error message.
7 Answers
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PHP - iterate on string characters
...ated array
foreach ($array as $char) {
echo $char;
}
You can check the PHP docs for more information: str_split
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Get operating system info
...perating system info. I have not been able to find out how to do that with PHP, and wanted to try to figure it out.
7 Answe...
Remove commas from the string using JavaScript
...aximumFractionDigits: 2
})
// Good Inputs
parseFloat(numFormatter.format('1234').replace(/,/g,"")) // 1234
parseFloat(numFormatter.format('123').replace(/,/g,"")) // 123
// 3rd decimal place rounds to nearest
parseFloat(numFormatter.format('1234.233').replace(/,/g,"")); // 1234.23
parseFloat(numFo...
correct way to define class variables in Python [duplicate]
...u'll see it more clearly with some code:
class MyClass:
static_elem = 123
def __init__(self):
self.object_elem = 456
c1 = MyClass()
c2 = MyClass()
# Initial values of both elements
>>> print c1.static_elem, c1.object_elem
123 456
>>> print c2.static_elem, c2.ob...