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How to mkdir only if a directory does not already exist?
...st to see that the directory does not exist, or suppress the "File exists" error that mkdir throws when it tries to create an existing directory.
...
Check if image exists on server using JavaScript?
... good, bad) {
var img = new Image();
img.onload = good;
img.onerror = bad;
img.src = imageSrc;
}
checkImage("foo.gif", function(){ alert("good"); }, function(){ alert("bad"); } );
JSFiddle
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...
Hibernate - A collection with cascade=”all-delete-orphan” was no longer referenced by the owning ent
...erenced distinctly points out creating a new HashSet but you can have this error anytime you reassign the set. For example:
public void setChildren(Set<SonEntity> aSet)
{
this.sonEntities = aSet; //This will override the set that Hibernate is tracking.
}
Usually you want to only "new" ...
How do I find out which process is locking a file using .NET?
... to determine file locker.");
try
{
const int ERROR_MORE_DATA = 234;
uint pnProcInfoNeeded = 0,
pnProcInfo = 0,
lpdwRebootReasons = RmRebootReasonNone;
string[] resources = new string[] { path }; // Just checking...
commandButton/commandLink/ajax action/listener method not invoked or input value not set/updated
...alue>
</context-param>
and you are also not seeing any googlable errors and/or warnings in browser's JavaScript console (press F12 in Chrome/Firefox23+/IE9+ to open the web developer toolset and then open the Console tab), then work through below list of possible causes.
Possible causes
U...
Database Diagram Support Objects cannot be Installed … no valid owner
I tried to create a database diagramm with SQL Server 2008, but an error occurs:
14 Answers
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Django: ImproperlyConfigured: The SECRET_KEY setting must not be empty
...ough. When I try to run ./manage.py runserver I am getting the following error:
25 Answers
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When is CRC more appropriate to use than MD5/SHA1?
When is it appropriate to use CRC for error detection versus more modern hashing functions such as MD5 or SHA1? Is the former easier to implement on embedded hardware?
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Does IE9 support console.log, and is it a real function?
...t not the DebugBar I got a message from latter that there was a JavaScript error (console is not defined).
– Simon A. Eugster
Sep 28 '12 at 5:21
...
Parsing boolean values with argparse
...ther solution using the previous suggestions, but with the "correct" parse error from argparse:
def str2bool(v):
if isinstance(v, bool):
return v
if v.lower() in ('yes', 'true', 't', 'y', '1'):
return True
elif v.lower() in ('no', 'false', 'f', 'n', '0'):
return F...