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The cast to value type 'Int32' failed because the materialized value is null
...ky abstraction" that yields unexpected behaviour.
One such case is null handling, where there can be unexpected nulls in different places. ...DefaultIfEmpty(0).Sum(0) can help in this (quite simple) case, where there might be no elements and sql's SUM returns null whereas c# expect 0.
A more gene...
Is it possible to declare a variable in Gradle usable in Java?
... in Java ?
Basically I would like to declare some vars in the build.gradle and then getting it (obviously) at build time. Just like a pre-processor macros in C/C++...
...
Clone Object without reference javascript [duplicate]
I have a big object with much data. And i want to clone this in other variable. When i set some param of the instance B has the same result in the original object:
...
How default .equals and .hashCode will work for my classes?
...t's (generally speaking; if you inherit from a class that redefined equals and/or hashCode, then you'll use that implementation instead).
From the documentation:
equals
The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, f...
How do I scroll to an element using JavaScript?
...e an anchor to "focus" the div. I.e:
<div id="myDiv"></div>
and then use the following javascript:
// the next line is required to work around a bug in WebKit (Chrome / Safari)
location.href = "#";
location.href = "#myDiv";
...
Does Python SciPy need BLAS?
...
The SciPy webpage used to provide build and installation instructions, but the instructions there now rely on OS binary distributions. To build SciPy (and NumPy) on operating systems without precompiled packages of the required libraries, you must build and then st...
ActionBar text color
...ncoding="utf-8"?>
<resources>
<style name="MyTheme" parent="@android:style/Theme.Holo.Light">
<item name="android:actionBarStyle">@style/MyTheme.ActionBarStyle</item>
</style>
<style name="MyTheme.ActionBarStyle" parent="@android:style/Widget.Holo.Light...
Error : The service is invalid
...
Xcode and the GDB connection is quite temperamental. The device and your Mac can become unsynchronised with each other. My checklist for this sort of thing:
Restart Xcode.
Delete the .app from your iOS device, do a Clean then Reb...
Type.GetType(“namespace.a.b.ClassName”) returns null
...
the type exists, it's in a different class library, and i need to get it by string name
– Omu
Dec 1 '09 at 9:58
28
...
Check to see if a string is serialized?
...
In case the passed string is not
unserializeable, FALSE is returned and
E_NOTICE is issued.
So, you have to check if the return value is false or not (with === or !==, to be sure not to have any problem with 0 or null or anything that equals to false, I'd say).
Just beware the notice : y...