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Why does Convert.ToString(null) return a different value if you cast null?

... There are 2 overloads of ToString that come into play here Convert.ToString(object o); Convert.ToString(string s); The C# compiler essentially tries to pick the most specific overload which will work with the input. A null value is convertible to a...
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When to use Cast() and Oftype() in Linq

...T for example: object[] objs = new object[] { "12345", 12 }; objs.Cast<string>().ToArray(); //throws InvalidCastException objs.OfType<string>().ToArray(); //return { "12345" } share | ...
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C# equivalent of the IsNull() function in SQL Server

... return Expression; } } //When Expression is string (Can not send Null value in string Expression public static string isEmpty(string Expression, string Value) { if (Expression == "") { return Value; } else { ...
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Get Android .apk file VersionName or VersionCode WITHOUT installing apk

... final PackageManager pm = getPackageManager(); String apkName = "example.apk"; String fullPath = Environment.getExternalStorageDirectory() + "/" + apkName; PackageInfo info = pm.getPackageArchiveInfo(fullPath, 0); Toast.makeText(this, "VersionCode : " + info.versi...
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How do I get formatted JSON in .NET using C#?

...yPrint { internal class Program { private static void Main(string[] args) { Product product = new Product { Name = "Apple", Expiry = new DateTime(2008, 12, 28), Price = 3.99M, ...
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JavaScript/jQuery to download file via POST with JSON data

... body, appends the iframe HTML, and sets the innerHTML of the page to that string. This will wipe out any event bindings your page has, amongst other things. Create an element and use appendChild instead. $.post('/create_binary_file.php', postData, function(retData) { var iframe = document.create...
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How to get the first word of a sentence in PHP?

I want to extract the first word of a variable from a string. For example, take this input: 22 Answers ...
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How to dynamic new Anonymous Class?

...ove fields on the fly. edit Sure you can: just cast it to IDictionary<string, object>. Then you can use the indexer. You use the same casting technique to iterate over the fields: dynamic employee = new ExpandoObject(); employee.Name = "John Smith"; employee.Age = 33; foreach (var propert...
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Python Unicode Encode Error

...ecause theres some foreign Unicode characters. Try to encode your unicode string as ascii first: unicodeData.encode('ascii', 'ignore') the 'ignore' part will tell it to just skip those characters. From the python docs: >>> u = unichr(40960) + u'abcd' + unichr(1972) >>> u.enco...
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Assigning code to a variable

...ould add "message" as a parameter (note that I changed Action to Action<string> in order to specify a single string parameter): Action<string> ButtonClicked = (message) => MessageBox.Show(message); ButtonClicked("hello world!"); ...