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The cast to value type 'Int32' failed because the materialized value is null
...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 general approach is to use ?? which will be translated to COALESCE whenever there is a r...
Best way to find if an item is in a JavaScript array? [duplicate]
...
As of ECMAScript 2016 you can use includes()
arr.includes(obj);
If you want to support IE or other older browsers:
function include(arr,obj) {
return (arr.indexOf(obj) != -1);
}
EDIT:
This will not work on IE6, 7 or 8 though. The be...
Test if a command outputs an empty string
...r success, non-zero for failure). For example:
files=$(ls -A)
if [[ $? != 0 ]]; then
echo "Command failed."
elif [[ $files ]]; then
echo "Files found."
else
echo "No files found."
fi
More info here.
share
...
Does Java support default parameter values?
...
answered Jun 15 '09 at 18:14
Kathy Van StoneKathy Van Stone
22.3k22 gold badges2929 silver badges3939 bronze badges
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Multiple queries executed in java in single statement
...
140
I was wondering if it is possible to execute something like this using JDBC.
"SELECT FROM * TAB...
PHP: Count a stdClass object
...urn the right number when I run the count($obj) function. The object has 30 properties, but the return on the count() function is say 1.
...
How to efficiently concatenate strings in go
...
880
New Way:
From Go 1.10 there is a strings.Builder type, please take a look at this answer for mo...
Drop shadow for PNG image in CSS
...s for IE.
.shadowed {
-webkit-filter: drop-shadow(12px 12px 25px rgba(0,0,0,0.5));
filter: url(#drop-shadow);
-ms-filter: "progid:DXImageTransform.Microsoft.Dropshadow(OffX=12, OffY=12, Color='#444')";
filter: "progid:DXImageTransform.Microsoft.Dropshadow(OffX=12, OffY=12, Color='#4...
Why in Java 8 split sometimes removes empty strings at start of result array?
... in Java 7 and Java 8. The code is retrieved from grepcode, for version 7u40-b43 and 8-b132.
Java 7
public String[] split(CharSequence input, int limit) {
int index = 0;
boolean matchLimited = limit > 0;
ArrayList<String> matchList = new ArrayList<>();
Matcher m = ma...