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When would you use a List instead of a Dictionary?

...que in dictionary. Consider this examples: List<KeyValuePair<int, string>> pairs = new List<KeyValuePair<int, string>>(); pairs.Add(new KeyValuePair<int, string>(1, "Miroslav")); pairs.Add(new KeyValuePair<int, string>(2, "Naomi")); pairs.Add(new KeyValuePair&l...
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Origin is not allowed by Access-Control-Allow-Origin

...le: public class HttpHeaderAttribute : ActionFilterAttribute { public string Name { get; set; } public string Value { get; set; } public HttpHeaderAttribute(string name, string value) { Name = name; Value = value; } public override void OnResultExecuted(Resu...
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C# How can I check if a URL exists/is valid?

...nt()) { client.HeadOnly = true; // fine, no content downloaded string s1 = client.DownloadString("http://google.com"); // throws 404 string s2 = client.DownloadString("http://google.com/silly"); } You would try/catch around the DownloadString to check for errors; no error? It e...
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Android get free size of internal/external memory

... android.os.Environment.MEDIA_MOUNTED); } public static String getAvailableInternalMemorySize() { File path = Environment.getDataDirectory(); StatFs stat = new StatFs(path.getPath()); long blockSize = stat.getBlockSizeLong(); long availableBlocks = ...
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Why is (object)0 == (object)0 different from ((object)0).Equals((object)0)?

... @280Z28 So? A similar case is that their Boolean.ToString method apparently contains hardcoded strings inside its function, rather than returning the publicly exposed Boolean.TrueString and Boolean.FalseString. It's irrelevant; The point is, == does the same thing as Referenc...
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typecast string to integer - Postgres

...hich has raw feeds in Varchar, I need to import a column in varchar into a string column. I tried using the <column_name>::integer as well as to_number(<column_name>,'9999999') but I am getting errors, as there are a few empty fields, I need to retrieve them as empty or null into the...
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Instance v state variables in react.js

...ld only be done by setState as suggested in a comment), React calls render and makes any necessary changes to the real DOM. Because the value of timeout has no effect on the rendering of your component, it shouldn't live in state. Putting it there would cause unnecessary calls to render. ...
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UISegmentedControl below UINavigationbar in iOS 7

...e navigation bar. Set the delegate of the toolbar to your view controller, and return UIBarPositionTopAttached in positionForBar:. You can see in the store app, if you perform an interactive pop gesture, that the segment bar does not move the same as the navigation bar. That's because they are not t...
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What is Serialization?

... So it turns it into a string? – NoName Oct 7 '19 at 21:17 1 ...
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What is a Manifest in Scala and when do you need it?

...tic type of a collection. For example, what if you wanted to treat a List[String] differently from other types of a List: def foo[T](x: List[T])(implicit m: Manifest[T]) = { if (m <:< manifest[String]) println("Hey, this list is full of strings") else println("Non-string...