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How to check 'undefined' value in jQuery
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Note that typeof always returns a string, and doesn't generate an error if the variable doesn't exist at all.
function A(val){
if(typeof(val) === "undefined")
//do this
else
//do this
}
share
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django - query filter on manytomany is empty
In Django is there a way to filter on a manytomany field being empty or null.
2 Answers
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Attempt by security transparent method 'WebMatrix.WebData.PreApplicationStartCode.Start()'
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For me this error was because I did NOT have Microsoft.AspNet.WebHelpers installed after updating from MVC 4 to MVC 5. It was fixed by installing the NuGet package
Install-Package -Id Microsoft.AspNet.WebHelpers
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How to mock ConfigurationManager.AppSettings with moq
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I believe one standard approach to this is to use a facade pattern to wrap the configuration ma...
How to retrieve all keys (or values) from a std::map and put them into a vector?
This is one of the possible ways I come out:
18 Answers
18
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if checkbox is checked, do this
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answered Oct 3 '13 at 20:05
Benny NeugebauerBenny Neugebauer
37.5k1818 gold badges179179 silver badges166166 bronze badges
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How to dump a dict to a json file?
... It throws " dumps() takes 1 positional argument but 2 were given" error
– Vijay Nirmal
Aug 8 '18 at 19:18
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show 4 more comments
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How do I restart nginx only after the configuration test was successful on Ubuntu?
... an Ubuntu server, the service crashes when a nginx configuration file has errors. On a multi-site server this puts down all the sites, even the ones without configuration errors.
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Find the most frequent number in a numpy vector
Suppose I have the following list in python:
12 Answers
12
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Convert Rows to columns using 'Pivot' in SQL Server
...you have the defined above logic with the @cols and @query ... there is an error.` Invalid object name 'cte3'.` how do you fix that. –
– Elizabeth
Mar 1 '16 at 18:59
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