带对象的转换器，数组通过函数传递变量

Question

在编码练习中，我需要构建一个加密货币转换器。

为了练习起见，它应该从一个将数据传递给其他函数的函数开始。只有第一个函数应该被调用级联到相应的结果。

1. addCurrency（将采用 3 个参数并检查是否存在名为 crypt 的数据库中的货币）
2. findcurrency（将从第一个函数中获取基本值并将它们传递给下一个函数）
3. converter（将进行实际转换
4. tellConversion（“您的 2 个 {COINS_NAME} 将收到 {AMOUNT} 美元”）

addCurrency 接受 3 个参数：硬币、其价值（硬币数量）和硬币数组（硬币数据库），因此示例调用可能如下所示

addCurrency({coin:'bitcoin', rate:8000}, 2, crypt)

如果硬币不在数据库中，它应该返回：

“新硬币 {YOUR_NEW_ADDED_COIN_GOES_HERE} 添加到数据库”

但硬币名称大写！！！并将硬币存放在地穴中。

如果硬币在数据库中，它应该返回

“您的 2 个 {COINS_NAME} 将收到 {AMOUNT} 美元”

这是我的代码。 有两个问题：不确定如何大写和转换器不起作用（不确定原因）。

谁能帮帮我？

var crypt = []; // define our database

var addCurrency = function (coin, value, crypt) {
    debugger;
    var indexObject = null; //helper variable to check coin in database

    //does the coin exist 
    for (var i = 0; i < crypt.length; i++) { //loop through the crypt in order to ...
        var obj = crypt[i].coin; //... set a variable with the current iterations coin name 
        if (obj == coin.coin) {//if that object happens to be the passed in coins'name ...
            indexObject = obj; //... set the value of indexObject to that value (want to store it for futre cod)
        }
    }

    //if coin not found, create a new one
    if(indexObject == null) { //... if the helper stays null ...
        //coin.coin = coin.coin.charAt(0).toUpperCase() + coin.coin.slice(1) //capitalize crypto currency

        indexObject = { //set index object with ...
            "coin": coin.coin, "rate": coin.rate //...this object patter
        }
        crypt.push(indexObject);
        return `New coin ${coin.coin} added to Database`
    //here passing between variable start. conversion rate is passed to findcurrency function
    } else {
        var passedOn = coin.rate
        var value = value
        findcurrency(passedOn, value)
    }
}

function findcurrency(passedOn, value) {
    converter(passedOn, value)
}

function converter(passedOn, value) {
    var converted = passedOn * value
    tellConversion(converted, value)
}

function tellConversion(converted, value) {
     return `You will receive ${converted} usd for your 2 ${value}`
}

Answer 1

您不会从 addCurrency、findcurrency 和转换器的 else 分支返回。

在这些语句的最后一个语句之前添加“return”，它应该可以工作。

例如：

var crypt = []; // define our database

var addCurrency = function (coin, value, crypt) {
    debugger;
    var indexObject = null; //helper variable to check coin in database

    //does the coin exist 
    for (var i = 0; i < crypt.length; i++) { //loop through the crypt in order to ...
        var obj = crypt[i].coin; //... set a variable with the current iterations coin name 
        if (obj == coin.coin) {//if that object happens to be the passed in coins'name ...
            indexObject = obj; //... set the value of indexObject to that value (want to store it for futre cod)
        }
    }

    //if coin not found, create a new one
    if(indexObject == null) { //... if the helper stays null ...
        //coin.coin = coin.coin.charAt(0).toUpperCase() + coin.coin.slice(1) //capitalize crypto currency

        indexObject = { //set index object with ...
            "coin": coin.coin, "rate": coin.rate //...this object patter
        }
        crypt.push(indexObject);
        return `New coin ${coin.coin} added to Database`
    //here passing between variable start. conversion rate is passed to findcurrency function
    } else {
        var passedOn = coin.rate
        var value = value
        return findcurrency(passedOn, value)
    }
}

function findcurrency(passedOn, value) {
    return converter(passedOn, value)
}

function converter(passedOn, value) {
    var converted = passedOn * value
    return tellConversion(converted, value)
}

function tellConversion(converted, value) {
     return `You will receive ${converted} usd for your 2 ${value}`
}