Javascript在特定索引处向Array附加元素

Question

我有一个动态生成的数组:

myArr = ["val0a", "val1a", "val2a"... "val600a"]

我在循环中将新数组值附加到此数组时遇到问题.追加后我的数组应如下所示:

myArr = ["val0a", "val1a val1b", "val2a val2b"... "val600a"]

请注意,新阵列和旧阵列的长度不同.

我怎样才能做到这一点？它必须是简单的东西,但我无法弄清楚.

Answer 1

您可以按照以下方式编写函数:

Array.prototype.appendStringToElementAtIndex = function(index, str) {
    if(typeof this[index] === 'undefined' || typeof this[index] !== 'string') return false;
    this[index] += ' ' + str;
};


myArr = ["val0a", "val1a", "val2a"];
myArr.appendStringToElementAtIndex(1, "val1b");

console.log(myArr.join(', ')); //val0a, val1a val1b, val2a