Detailed explanation of the use of the foreach () method in JavaScript

This article mainly introduces the use of the foreach () method in JavaScript, which is the basic knowledge in the learning of JS, the need of friends can refer to the following

The ForEach () method of a JavaScript array invokes each element in the array.

Grammar

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1	Array.foreach (callback[, Thisobject]);

The following are the details of the parameters:

Callback: Function tests each element of an array.

Thisobject: Object is used as the execution callback.

return value:

Returns the creation of an array.

Compatibility:

This approach is a JavaScript extension to the ECMA-262 standard, so it may not exist in other implementations of the standard. To make it work, you need to add the top of the following scripting code:

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if (! Array.prototype.forEach) {Array.prototype.forEach = function (Fun/*, thisp*/) {var len = this.length; if (typeof fun!=   "function") throw new TypeError (); var thisp = arguments[1]; for (var i = 0; i < len; i++) {if (i) Fun.call (Thisp, this[i], I, this); }

Example:

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This will produce the following results:

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[0 ' is ' [1] is 5 [2] are 8 [3] is 130 [4] is a