我不知道如何解决我的反向数组/字符串

Question

so I need to be able to enter a string and have it reversed. I must have one library JS file and one regular JS file. Here is my library JS file:

function reverseString(string) {
    var reversedString= "";
    for(var i = string.length -; i >=; --i) {
    reversedString = reversedString + string[i];
    }
    return reversedString;
}

and here is my regular one

var stringEntered = prompt("Enter a string:")
var newString = reverseString(stringEntered);
document.write("the reverse of the string \" + stringEntered + \ " is \" + newString + ".")

I entered it the exact same way my professor showed us, and I when I try to run my HTML file (which is coded to call both these files), nothing happens. What am I missing?

Answer 1

There're a lot of syntax issues. Here's a working code:

 function reverseString(string) { var reversedString = ""; // This loop had a lot of basic syntax issues and also // "i" was starting from the length value, while a string // is a character array and array indexes start from 0 instead of 1 for (var i = string.length - 1; i >= 0; --i) { reversedString = reversedString + string[i]; } return reversedString; } var stringEntered = prompt("Enter a string:"); var newString = reverseString(stringEntered); // Here I found a mess of "/" characters // I've changed the horrible document.write with alert so you can check the result without opening the debugger... alert("the reverse of the string " + stringEntered + " is " + newString + ".") 

Answer 2

Here is a concise method of reversing a string:

 function reverseString(string) { return string.split('').reverse().join(''); } var str = prompt("Enter a string", "a racecar dad"); alert(reverseString(str)); 

Turn it into an array, reverse the array, turn it back into a string.

Edit : Sorry, didn't see @SidneyLiebrand's comment telling you to do the same.