The foreach array method in JavaScript uses the example _ basics

The Array.prototype.forEach () method lets each item of an array perform a given function once. -mdn

Suppose there was such a scene that you got such an array of

[
{symbol: "XFX", price:240.22, volume:23432},
{symbol: "TNZ", price:332.19, volume:234},
{symbol: "Jxj", price:120.22, volume:5323},
]

You need to create a new array for symbol, which is

["XFX", "TNZ", "JXJ"]
Can generally be implemented in a For loop:

function Getstocksymbols (stocks) {
 var symbols = [], stock
   ,
   i;
   
 for (i = 0; i < stocks.length i++) {The stock
  = stocks[i];
  Symbols.push (Stock.symbol);
 }

 return symbols;
}

var symbols = Getstocksymbols ([
 {symbol: "XFX", price:240.22, volume:23432},
 {symbol: "TNZ", price:332.19, volume:234},
 {symbol: "Jxj", price:120.22, volume:5323},
]);

Output: "[/" xfx/"," tnz/"," jxj/"]"

You can also use the array's foreach method to simplify the code, and their output is exactly the same.

function Getstocksymbols (stocks) {
 var symbols = [];

 Stocks.foreach (function (stock) {
  Symbols.push (stock.symbol);
 });

 return symbols;
}