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Best way to check if a Data Table has a null value in it
...
Try comparing the value of the column to the DBNull.Value value to filter and manage null values in whatever way you see fit.
foreach(DataRow row in table.Rows)
{
object value = row["ColumnName"];
if (value == DBNull.Value)
// do something
else
// do something else
}
...
Batch: Remove file extension
...ailable:
Variable with modifier Description
%~I Expands %I which removes any surrounding
quotation marks ("").
%~fI Expands %I to a fully qualified path name.
%~dI Expands %I to a drive letter only.
%~pI ...
Run JavaScript code on window close or page refresh?
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There is both window.onbeforeunload and window.onunload, which are used differently depending on the browser. You can assing them either by setting the window properties to functions, or using the .addEventListener:
window.onbeforeunload = function(){
// Do...
Why use @PostConstruct?
...s are injected. In the @PostConstruct method the bean is fully initialized and you can use the dependencies.
because this is the contract that guarantees that this method will be invoked only once in the bean lifecycle. It may happen (though unlikely) that a bean is instantiated multiple times by th...
Check play state of AVPlayer
...ItemDidPlayToEndTimeNotification
object:<#A player item#>];
And to track playing you can:
"track changes in the position of the playhead in an AVPlayer object" by using addPeriodicTimeObserverForInterval:queue:usingBlock: or addBoundaryTimeObserverForTimes:queue:usingBlock:.
Exampl...
Android: Coloring part of a string using TextView.setText()?
... coloring a part of the text (or making it bold, italic, transparent, etc.)and not the rest. For example:
13 Answers
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HttpURLConnection timeout settings
...as a setConnectTimeout method.
Just set the timeout to 5000 milliseconds, and then catch java.net.SocketTimeoutException
Your code should look something like this:
try {
HttpURLConnection.setFollowRedirects(false);
HttpURLConnection con = (HttpURLConnection) new URL(url).openConnection();...
What do the parentheses around a function name mean?
...essary parentheses around function names is when there are both a function and a function-like macro with the same name, and the programmer wants to prevent macro expansion.
This practice may seem a little odd at first, but the C library sets a precedent by providing some macros and functions with ...
Delete all records in a table of MYSQL in phpMyAdmin
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Go to your db -> structure and do empty in required table.
See here:
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How do I create multiple submit buttons for the same form in Rails?
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You can create multiple submit buttons and provide a different value to each:
<% form_for(something) do |f| %>
..
<%= f.submit 'A' %>
<%= f.submit 'B' %>
..
<% end %>
This will output:
<input type="submit" value="A" i...