javascript - 我只希望此函数提醒您在遍历bookStore Array而不是在每个索引处都找不到一次该书。

function checkStore(string) {
    for (var i = 0; i < BookStore.length; i++) {
        if (BookStore[i].title === string) {
            prompt('We found your book! ' + string + ', by ' + BookStore[i].author +
                '. It costs ' + BookStore[i].price +
                ' would you like to add it to your cart?');
        } else {
            alert('Sorry ' + string + ' was not found, try another title?');
        }
    }
}

这就是发生的情况，可以说BookStore.length =6。如果BookStore[i].title === string在索引4处为true，这就是我得到的

'Sorry ' + string + ' was not found, try another title?'
'Sorry ' + string + ' was not found, try another title?'
'Sorry ' + string + ' was not found, try another title?'
'Sorry ' + string + ' was not found, try another title?'
'We found your book! ' + string + ', by ' + BookStore[i].author +
                    '. It costs ' + BookStore[i].price +
                    ' would you like to add it to your cart?'
'Sorry ' + string + ' was not found, try another title?'

如果不正确，我如何只打印一次'Sorry ' + string + ' was not found, try another title?'

'We found your book! ' + string + ', by ' + BookStore[i].author +
                        '. It costs ' + BookStore[i].price +
                        ' would you like to add it to your cart?'

本身何时成立？

谢谢！

最佳答案

Array.prototype.some()解决方案：

function checkStore(string) {
    var book;
    if (BookStore.some(function (b) {
        return b.title === string && (book = b);
    })) {
        prompt('We found your book! ' + string + ', by ' + book.author + '. It costs ' + book.price + ' would you like to add it to your cart?');
    } else {
        alert('Sorry ' + string + ' was not found, try another title?');
    }
}