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In this article, the editor introduces in detail "foreach is not in es6". The content is detailed, the steps are clear, and the details are handled properly. I hope this "foreach is not in es6" article can help you solve your doubts.

Foreach is not the method of es6. Foreach is a method that traverses an array in es3, calling each element of the array and passing it to the callback function for processing, the syntax "array.forEach (current element, index, array) {...}"; this method does not handle empty arrays.

The operating environment of this tutorial: windows7 system, ECMAScript version 3, Dell G3 computer.

Foreach is not the method of es6.

Foreach is a method of traversing an array in es3.

The forEach () method invokes each element of the array and passes the element to the callback function for processing.

Array.forEach (function (currentValue, index, arr) {...})

CurrentValue is required. Current element

Index is optional. The index value of the current element.

Arr is optional. The array object to which the current element belongs.

Return value: undefined

Example 1: calculate the sum of all the elements in the array

Var sum = 0 numbers = [65, 44, 12, 4]; numbers.forEach (function (item) {sum + = item; console.log (sum);})

Example 2: multiply all values in the array by the number 3

Var sum = 0 numbers = [65, 44, 12, 4]; numbers.forEach (function (item,index,arr) {item = item * 3; console.log (item);})

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