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How can I check for an empty/undefined/null string in JavaScript?
...e !!(not not) operator.
if(!!str){
// Some code here
}
Or use type casting:
if(Boolean(str)){
// Code here
}
Both do the same function. Typecast the variable to Boolean, where str is a variable.
It returns false for null,undefined,0,000,"",false.
It returns true for string "0" and whi...
Multiple Updates in MySQL
...ice for dynamic updating too. For example, I used that solution in loop in php: $commandTxt = 'UPDATE operations SET chunk_finished = CASE id '; foreach ($blockOperationChecked as $operationID => $operationChecked) $commandTxt .= " WHEN $operationID THEN $ope...
How can I define an interface for an array of objects with Typescript?
...erface, eg. id?: number; label?: string; key?: any the best way to avoid a casting issue if you use less properties than what is defined in the interface? Ie. I may not specify key in the typed array setup.
– GONeale
Feb 1 '16 at 4:48
...
Programmatically Lighten or Darken a hex color (or rgb, and blend colors)
...
A PHP version for those who need it: gist.github.com/chaoszcat/5325115#file-gistfile1-php
– Lionel Chan
Apr 6 '13 at 6:28
...
How to parse a string into a nullable int
...this in one line, using the conditional operator and the fact that you can cast null to a nullable type (two lines, if you don't have a pre-existing int you can reuse for the output of TryParse):
Pre C#7:
int tempVal;
int? val = Int32.TryParse(stringVal, out tempVal) ? Int32.Parse(stringVal) : (in...
Getting time elapsed in Objective-C
...
Anyone know why there is a redundant (void) cast on the mach_timebase_info call?
– Simon Tillson
Dec 10 '13 at 10:57
...
How to avoid “RuntimeError: dictionary changed size during iteration” error?
...ot iterate through a dictionary while its changing during for loop. Make a casting to list and iterate over that list, it works for me.
for key in list(d):
if not d[key]:
d.pop(key)
share
...
How to check if an email address exists without sending an email?
I have come across this PHP code to check email address using SMTP without sending an email .
14 Answers
...
DateTime format to SQL format using C#
...
Yeah, on the official page CAST and CONVERT (Transact-SQL), they use the name "ODBC canonical" for the form with a space separating yyyy-MM-dd from the time of day, and the name "ISO8601" for the form where the separating character is a T. But yes, bot...
Can you nest html forms?
...1_n2
input_Form2_n2
Implementation:
<form id="Form1" action="Action1.php" method="post"></form>
<form id="Form2" action="Action2.php" method="post"></form>
<input type="text" name="input_Form1_n1" form="Form1" />
<input type="text" name="input_Form2_n1" form="For...