This contains 6 elements namely Apple, Mango, Grapes, Orange, Fig and Cherry.The function checkValue takes 2 parameters as input, the value that needs to be searched and the array in which the value needs to be searched.Using a for loop the function compares each element of the array ...
Sometimes, we need to check if an array contains any null values. For this, we can use the Array.prototype.includes() function, which determines whether an array includes a certain value among its entries.Here's how to do it:let mixedArray = [true, null, false, true]; let contains...
let myString = "John Doe"; if (typeof myString === "string") { console.log("This variable is a string"); } else { console.log("This variable is not a string"); } Indeed, the myString is a string: This variable is a string Note: Even if the variable contains a number th...
if (typeof v === "undefined") { // no variable "v" is defined in the current scope // *or* some variable v exists and has been assigned the value undefined } else { // some variable (global or local) "v" is defined in the current scope // *and* it contains a value other...
The exampleButton variable is only populated after the component is rendered. If an unpopulated ElementReference is passed to JS code, the JS code receives a value of null. To manipulate element references after the component has finished rendering, use the OnAfterRenderAsync o...
When a user does not assign a value to a variable, it is of type undefined. The undefined type is a primitive type that contains only a single value, i.e., undefined. When users declare a variable but do not initialize it, i.e., it means the variable has a value assigned to it,...
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includes()Check if an array contains the specified element indexOf()Search the array for an element and returns its position isArray()Checks whether an object is an array join()Joins all elements of an array into a string keys()Returns a Array Iteration Object, containing the keys of the ...
As an example of an analysis using basic blocks, BasicBlock.isLiveAtEntry(v, u) determines whether variable v is live at the entry of the given basic block, and if so binds u to a use of v that refers to its value at the entry. We can use it to find global variables that are ...
Note: the assignment // value of `true` is not hoisted. function example() { console.log(declaredButNotAssigned); // => undefined var declaredButNotAssigned = true; } // the interpreter is hoisting the variable // declaration to the top of the scope, // which means our example could...