javascript将数组连接到另一个

Question

我想编写一个函数来将数组连接到另一种但不同的方式：var myNumbers = [10,20,3,4,2]var myOperations = ['+','-','*','/']我希望运算符位于 myNumbers 元素之间：10+20-3*4/2 = 54

Answer 1

其他成员已经指出了一些重复的问题，他们可以帮助你。请在下面找到我为您的问题制定的解决方案。

var numbersAndOperations = myNumbers.map((a, i) => myOperations[i] ? [a, myOperations[i]] : [a])

/* this makes a 2 levels deep array from your 2 and avoids any undefined values through a ternary operator.

If you don't know ternary operators they are a shorthand for an if condition.

[[10, "+"], [20, "-"], [3, "*"], [4, "/"], [2]] */

const myMathString = numbersAndOperations.flat(2).join(',').replace(/,/g, '')

// this turns it into a string and remove the comas: "10+20-3*4/2"

function mathEval(mathString) { // this hack evaluates your math function and immediately returns a result.

  return new Function('return ' + mathString)();

}

console.log(mathEval(myMathString)); // 24. The result is actually 24 because * and / are evaluated before the + and -

希望它有帮助:)