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How do I handle newlines in JSON?
...N spec at ietf.org/rfc/rfc4627.txt contains this sentence in section 2.5: "All Unicode characters may be placed within the quotation marks except for the characters that must be escaped: quotation mark, reverse solidus, and the control characters (U+0000 through U+001F)." Since a newline is a contro...
[A]System.Web.WebPages.Razor.Configuration.HostSection cannot be cast to… web.config issue
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I am using VS2013, MVC 5.2.2.0, Web Api 2. I have just changed the all versions from 2.0.0.0 to 3.0.0.0 of the following section of Web.config resides inside the View folder of my project.
<configSections>
<sectionGroup name="system.web.webPages.razor" type="System.Web.WebPages.Raz...
What is the best way to compare floats for almost-equality in Python?
...the magnitudes of the two arguments; as the values get larger, so does the allowed difference between them while still considering them equal.
abs_tol is an absolute tolerance that is applied as-is in all cases. If the difference is less than either of those tolerances, the values are considered eq...
How can I center an absolutely positioned element in a div?
...html> element doesn't have a height specified so it takes the height of all the content in the document, which is nothing because the only content is absolutely-positioned (taken out of content flow). Adding height: 100% to the <html> element makes a difference to this.
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How to read an external local JSON file in JavaScript?
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You cannot make a AJAX call to a local resource as the request is made using HTTP.
A workaround is to run a local webserver, serve up the file and make the AJAX call to localhost.
In terms of helping you write code to read JSON, you should read th...
How do I get the height and width of the Android Navigation Bar programmatically?
...r). You have to find out separately if and where the navigation bar is actually showing, e.g. by testing for the presence of a physical menu button. Maybe you can find some other way in the Android souce code at android.googlesource.com/platform/frameworks/base/+/…
– user1494...
How do you copy a record in a SQL table but swap out the unique id of the new row?
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Any fields not specified should receive their default value (which is usually NULL when not defined).
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How important is the order of columns in indexes?
... 3, the optimizer wouldn't even use the index, because it's not helpful at all in narrowing down the result sets. Anytime you're in a query, narrowing down the number of results to deal with before the next step means better performance.
Since the index is also stored this way, there's no backtrac...
Detect Retina Display
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In order to detect the Retina display reliably on all iOS devices, you need to check if the device is running iOS4+ and if the [UIScreen mainScreen].scale property is equal to 2.0. You CANNOT assume a device is running iOS4+ if the scale property exists, as the iPad 3.2 als...
Remove directory which is not empty
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There is a module for this called rimraf (https://npmjs.org/package/rimraf). It provides the same functionality as rm -Rf
Async usage:
var rimraf = require("rimraf");
rimraf("/some/directory", function () { console.log("done"); });
Sync usage:
rimr...