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Get data from fs.readFile
...Raynos said, the function you have defined is an asynchronous callback. It doesn't execute right away, rather it executes when the file loading has completed. When you call readFile, control is returned immediately and the next line of code is executed. So when you call console.log, your callback ha...
JPA or JDBC, how are they different?
I am learning Java EE and I downloaded the eclipse with glassfish for the same. I saw some examples and also read the Oracle docs to know all about Java EE 5. Connecting to a database was very simple. I opened a dynamic web project, created a session EJB , I used EntityManager and with the get meth...
How to get image size (height & width) using JavaScript?
...ered Mar 9 '09 at 14:44
Josh StodolaJosh Stodola
76.3k4242 gold badges176176 silver badges219219 bronze badges
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Unable to cast object of type 'System.DBNull' to type 'System.String`
...countNumber.ToString()
EDIT: Haven't paid attention to ExecuteScalar. It does really return null if the field is absent in the return result. So use instead:
return (accountNumber == null) ? string.Empty : accountNumber.ToString()
...
Fragments onResume from back stack
...a time).
In MyActivity, add this listener:
getSupportFragmentManager().addOnBackStackChangedListener(getListener());
(As you can see I'm using the compatibility package).
getListener implementation:
private OnBackStackChangedListener getListener()
{
OnBackStackChangedListener resul...
How to kill a process running on particular port in Linux?
I tried to close the tomcat using ./shutdown.sh from tomcat /bin directory. But found that the server was not closed properly. And thus I was unable to restart My tomcat is running on port 8080 .
...
Count the number of occurrences of a string in a VARCHAR field?
...
This should do the trick:
SELECT
title,
description,
ROUND (
(
LENGTH(description)
- LENGTH( REPLACE ( description, "value", "") )
) / LENGTH("value")
) AS count ...
Optimistic vs. Pessimistic locking
...y where you read a record, take note of a version number (other methods to do this involve dates, timestamps or checksums/hashes) and check that the version hasn't changed before you write the record back. When you write the record back you filter the update on the version to make sure it's atomic....
Detecting an “invalid date” Date instance in JavaScript
...
Here's how I would do it:
if (Object.prototype.toString.call(d) === "[object Date]") {
// it is a date
if (isNaN(d.getTime())) { // d.valueOf() could also work
// date is not valid
} else {
// date is valid
}
} else {
// not...
Select2 dropdown but allow new values by user?
I want to have a dropdown with a set of values but also allow the user to "select" a new value not listed there.
9 Answers...