计算内部二维数组的值-JavaScript

Question

我有一个二维数组。我正在尝试计算内部数组中的值。我知道JS array.length。但是这样做会testData.length产生5。这是正确的。但是，我想计算每个子数组中的项目数。

testData[0].length将产生6。但是如何动态计算每个子数组？（因为它会改变）。

var testData = [["column1","test1","test1","tea","party", "water bottle"],
                ["column2","test2","test2","test2 test2"],
                ["column3","test2","test2","test2 test2 "],
                ["column4","test2","test2 test2f asdfsdf"],
                ["column5","test2","test2 test2f asdfsdfasdfasdfasa asda asdfsas"]
]

Answer 1

用途reduce：

ES6：

testData.reduce((count, row) => count + row.length, 0);

ES5：

testData.reduce(function(count, row) { 
    return count + row.length;
}, 0);

https://developer.mozilla.org/de/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce

Answer 2

使用Array.forEach

s=0;
testData.forEach(function(e,i,a){s += e.length; });

另请参阅：https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Array/forEach

Answer 3

var testData = [
    ["column1","test1","test1","tea","party", "water bottle"],
    ["column2","test2","test2","test2 test2"],
    ["column3","test2","test2","test2 test2 "],
    ["column4","test2","test2 test2f asdfsdf"],
    ["column5","test2","test2 test2f asdfsdfasdfasdfasa asda asdfsas"]
];
for(var i=0;i < testData.length;i++){
  for(var j=0;j<testData[i].length;j++){
    alert(testData[i][j]);
  }
}