I don’t really have an answer, but according to Nicholas C. Zakas, page 30 of his book “Professional JavaScript for Web Developers“: When defining a variable that is meant to later hold an object, it is advisable to initialize the variable to null as opposed to anything else. That way, you can explicitly check for … Read more
Generic answer This error is caused when you call a function that expects an Object as its argument, but pass undefined or null instead, like for example Object.keys(null) Object.assign(window.UndefinedVariable, {}) As that is usually by mistake, the solution is to check your code and fix the null/undefined condition so that the function either gets a … Read more
Java will always try to use the most specific applicable version of a method that’s available (see JLS ยง15.12.2). Object, char[] and Integer can all take null as a valid value. Therefore all 3 version are applicable, so Java will have to find the most specific one. Since Object is the super-type of char[], the … Read more
Use object.ReferenceEquals(person1, null) or the new is operator instead of the == operator: public static bool operator ==(Person person1, Person person2) { if (person1 is null) { return person2 is null; } return person1.Equals(person2); }
This worked for me json_decode( preg_replace(‘/[\x00-\x1F\x80-\xFF]/’, ”, $json_string), true );
It’s language specific, but in PHP : Null means “nothing“. The var has not been initialized. False means “not true in a boolean context“. Used to explicitly show you are dealing with logical issues. 0 is an int. Nothing to do with the rest above, used for mathematics. Now, what is tricky, it’s that in … Read more
I just did some tests of the four options that I know about. Measure-Command {$(1..1000) | Out-Null} TotalMilliseconds : 76.211 Measure-Command {[Void]$(1..1000)} TotalMilliseconds : 0.217 Measure-Command {$(1..1000) > $null} TotalMilliseconds : 0.2478 Measure-Command {$null = $(1..1000)} TotalMilliseconds : 0.2122 ## Control, times vary from 0.21 to 0.24 Measure-Command {$(1..1000)} TotalMilliseconds : 0.2141 So I would … Read more
You need to replace !string.IsNullOrWhiteSpace(b.Diameter) with !(b.Diameter == null || b.Diameter.Trim() == string.Empty) For Linq to Entities this gets translated into: DECLARE @p0 VarChar(1000) = ” … WHERE NOT (([t0].[Diameter] IS NULL) OR (LTRIM(RTRIM([t0].[Diameter])) = @p0)) and for Linq to SQL almost but not quite the same DECLARE @p0 NVarChar(1000) = ” … WHERE NOT … Read more
In SQL, a comparison between a null value and any other value (including another null) using a comparison operator (eg =, !=, <, etc) will result in a null, which is considered as false for the purposes of a where clause (strictly speaking, it’s “not true”, rather than “false”, but the effect is the same). … Read more
You can compare nullable boolean with true, false or null using equality operator: var b: Boolean? = null if (b == true) { // b was not null and equal true } if (b == false) { // b is false } if (b != true) { // b is null or false }