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javascript set a variable if undefined
I know that I can test for a javascript variable and then define it if it is undefined, but is there not some way of saying
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Can you have multiple $(document).ready(function(){ … }); sections?
...
You can have multiple ones, but it's not always the neatest thing to do. Try not to overuse them, as it will seriously affect readability. Other than that , it's perfectly legal. See the below:
http://www.learningjquery.com/2006/09/multiple-document-ready
Try this out:
$(docum...
XMLHttpRequest Origin null is not allowed Access-Control-Allow-Origin for file:/// to file:/// (Serv
...nd then included the data in the html like normal javascript:
<div id="test"></div>
<script src="base64_data.js"></script>
<script>
data = atob(base64_data);
var sqldb = new SQL.Database(data);
// Database test code from the sql.js project
var test = s...
How do I get the different parts of a Flask request's url?
...nother example:
request:
curl -XGET http://127.0.0.1:5000/alert/dingding/test?x=y
then:
request.method: GET
request.url: http://127.0.0.1:5000/alert/dingding/test?x=y
request.base_url: http://127.0.0.1:5000/alert/dingding/test
request.url_charset: ...
How to convert SecureString to System.String?
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@radbyx In a quick and dirty test setup, I can call it 1000 times in 76ms. The first invocation takes 0.3 ms and subsequent invocations ~0.07ms. How large is your secure string and which version of the framework are you using?
– Ras...
Null coalescing in powershell
...t a variable is defined first. If you set $myval = $null before doing the test, the error should go away.
– StephenD
Jul 4 '19 at 8:06
1
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Determine if Python is running inside virtualenv
...at() != sys.prefix
If you only care about supported Python versions and latest virtualenv, you can replace get_base_prefix_compat() with simply sys.base_prefix.
Using the VIRTUAL_ENV environment variable is not reliable. It is set by the virtualenv activate shell script, but a virtualenv can be use...
What really happens in a try { return x; } finally { x = null; } statement?
...finally {
...
}
return tmp;
for example (using reflector):
static int Test() {
try {
return SomeNumber();
} finally {
Foo();
}
}
compiles to:
.method private hidebysig static int32 Test() cil managed
{
.maxstack 1
.locals init (
[0] int32 CS$1$0000...
Find size of object instance in bytes in c#
... Marshal.ReadInt32(type.TypeHandle.Value, 4) works for x86 and x64. I only tested struct and class types. Keep in mind that this returns the boxed size for value types. @Pavel Maybe you could update your answer.
– jnm2
Mar 1 '15 at 1:52
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Regex to replace multiple spaces with a single space
...unning 100k string replacements.
I encourage you to do your own profiling tests with firebug, if you think performance is an issue. Humans are notoriously bad at predicting where the bottlenecks in their programs lie.
(Also, note that IE 8's developer toolbar also has a profiler built in -- it mi...