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How do I check in JavaScript if a value exists at a certain array index?
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Using only .length is not safe and will cause an error in some browsers. Here is a better solution:
if(array && array.length){
// not empty
} else {
// empty
}
or, we can use:
Object.keys(__array__).length
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ASP.NET MVC 404 Error Handling [duplicate]
I've made the changes outlined at 404 Http error handler in Asp.Net MVC (RC 5) and I'm still getting the standard 404 error page. Do I need to change something in IIS?
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Django Forms: if not valid, show form with error message
...e view when the form is not valid then in template you can access the form errors using form.errors.
{% if form.errors %}
{% for field in form %}
{% for error in field.errors %}
<div class="alert alert-danger">
<strong>{{ error|escape }}</stron...
Preventing console window from closing on Visual Studio C/C++ Console application
... (15.9.4) there is an option:
Tools->Options->Debugging->Automatically close the console
The corresponding fragment from the Visual Studio documentation:
Automatically close the console when debugging stops:
Tells Visual Studio to close the console at the end of a debugging session.
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How to correctly save instance state of Fragments in back stack?
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This is not related to question, onSaveInstance is not called when fragment is putted to backstack
– Tadas Valaitis
Jan 7 '15 at 10:14
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SQLite error 'attempt to write a readonly database' during insert?
...QLite file itself is not the same as the user running the script. Similar errors can occur if the entire directory path (meaning each directory along the way) can't be written to.
Who owns the SQLite file? You?
Who is the script running as? Apache or Nobody?
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Disposing WPF User Controls
...sable, and I would like to ensure that its dispose method will always get called once the containing window/application is closed. However, UserControl is not disposable. I tried implementing the IDisposable interface and subscribing to the Unloaded event but neither get called when the host applica...
“Prevent saving changes that require the table to be re-created” negative effects
...rform an operation that causes the table to be re-created, you receive the error message that is mentioned in the "Symptoms" section. However, if you turn off this option, the existing change tracking information is deleted when the table is re-created. Therefore,Microsoft recommend that you do not ...
docker error: /var/run/docker.sock: no such file or directory
...passed into the boot2docker VM runs as root by default.
You're seeing the error when you're running as sudo because sudo doesn't have the DOCKER_HOST env set, only your user does.
You can confirm this by doing a:
$ env
Then a
$ sudo env
And looking for DOCKER_HOST in each output.
As for hav...
How can I get a java.io.InputStream from a java.lang.String?
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You might be right. I originally made it a comment probably because it wasn't an actual answer to OP's question.
– Andres Riofrio
Jul 15 '13 at 18:52
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