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Unable to cast object of type 'System.DBNull' to type 'System.String`
...Number : 0;
If you know for sure that your resultset will always have at least one row (e.g. SELECT COUNT(*)...), then you can skip the check for null.
In your case the error message "Unable to cast object of type ‘System.DBNull’ to type ‘System.String`" indicates that the first column of y...
What are all the different ways to create an object in Java?
...ys).
Non-compile time constant string concatenation (happens to produce at least four objects, on a typical implementation).
Causing an exception to be created and thrown by the runtime. For instance throw null; or "".toCharArray()[0].
Oh, and boxing of primitives (unless cached), of course.
JDK8 sh...
Jquery bind double click and single click separately
... you shouldn't anymore nowadays IMO) but I try to achieve functionality at least on IE9 - this is the browser anyone can have (no OS limitations) and which has good JS support.
– Dennis98
Jul 4 '15 at 14:37
...
Convert Array to Object
...ding. Will require either a transpiler(Babel) or an environment running at least ES6.
console.log(
{ ...['a', 'b', 'c'] }
)
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How do I install the OpenSSL libraries on Ubuntu?
...
You want the openssl-devel package.
At least I think it's -devel on Ubuntu. Might be -dev. It's one of the two.
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How to clear the cache of nginx?
...tly has some real trouble when run in a virtual machine environment, or at least when run through Virtualbox. Turning this config off in nginx causes the static file to be served via a different method and your changes will be reflected immediately and without question
It is related to this bug: h...
ASP.NET MVC Conditional validation
...ing Password
{
get;
set;
}
}
At last but not the least , register adapter for your attribute so that it can do client side validation (I put it in global.asax, Application_Start)
DataAnnotationsModelValidatorProvider.RegisterAdapter(typeof(RequiredIfAttribute),typeof(Req...
const char * const versus const char *?
...
@R..: Well, at least for me it's not. Reading from right to left, I get "pointer to const char". For me, it just feels better that way.
– Xeo
Feb 9 '11 at 20:49
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Remove white space below image [duplicate]
...parent in the case of the parent and img both having `display: inline`, at least you can't see the parent anymore.
cons:
Less efficient code.
This assumes "correct" markup; if the img has text node siblings, they won't show up.
3) Setting line-height: 0 on the parent element:
.parent {
li...
Using LINQ to concatenate strings
...nd, but using LINQ to actually get the end result would be bad, to say the least, if not outright stupid
– Jason Bunting
Sep 23 '08 at 20:03
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