在警报提示中使用时代替变量字符串"[object Object]"

Question

我最近从常规的JavaScript提示切换到了jQuery插件的"Alertify"提示。但是，当我将一个变量定义为提示的响应，并在稍后的警报中使用该变量时，它会打印"[object object]"。经过几个小时的谷歌搜索和测试，我仍然没有找到答案。

这是我的代码：

do {
    var fullLoop = false;
    var user = alertify.prompt("What is your name?", function (e, str) {
        if (e) {
            user.toUpperCase();
            if (str.length === 0) {
                alertify.alert("Please enter your name.");
                fullLoop = true;
            }
        } else {
            alertify.alert("Please enter your name.");
            fullLoop = true;
        }
    }, "Name");
    do {
        var bestLoop = false;
        var best = alertify.prompt("So " + user + ", what is your greatest ability, STRENGTH, SPEED, or SMARTS?", function (e, str) {
        if (e) {
            best.toUpperCase();
            if (best === "STRENGTH" || best === "SPEED" || best === "SMARTS") {
            var offset = options.indexOf(best);
            if (offset != -1) {
                options.splice(offset, 1);
            }
        } else {
            alert("Please choose either STRENGTH, SPEED, or SMARTS as your greatest ability.");
            bestLoop = true;
        }
        } else {
            alertify.alert("Please choose either STRENGTH, SPEED, or SMARTS as your greatest ability.");
            bestLoop = true;
        }
    }, "Greatest Ability");
    } while (bestLoop);
    alertify.alert("Great! So " + best + " is yor greatest ability.");
} while (fullLoop);

你可以在这里看到我遇到的错误。

我还注意到，我关于字符串的if语句被忽略了，我假设存在连接，但它是什么？我没有发现任何错误，所以我是否错误地使用了Alertify？

Answer 1

您对alertify插件的使用是错误的，因为prompt方法是异步方法，所有使用的操作都必须在回调中完成。

缩小版如下

var options = ["STRENGTH", "SPEED", "SMARTS"];
alertify.alert("Before we begin our journey, let's learn a little bit  about you.");
alertify.prompt("What is your name?", function (e, str) {
    if (e) {
        var  user = str.toUpperCase();
        alertify.prompt("So " + user + ", what is your greatest ability, STRENGTH, SPEED, or SMARTS?", function (e, str) {
            if (e) {
                var best = str.toUpperCase();
                if (best === "STRENGTH" || best === "SPEED" || best === "SMARTS") {
                    var offset = options.indexOf(best);
                    if (offset != -1) {
                        options.splice(offset, 1);
                    }
                    alertify.alert("Great! So " + best + " is yor greatest ability.");        
                } else {
                }
            } else {
            }
        }, "Greatest Ability");
    } else {
    }
}, "Name");

演示：Fiddle

Answer 2

我对alterify了解不多，但看起来你正在尝试显示一个JSON对象。试试JSON.stringfy（user），看看你得到了什么。可能有点像

{ "Name": "Paul" }

如果是这样，你会想做

alertify.prompt("So " + user.Name + ", what is your greatest ability, STRENGTH, SPEED, or SMARTS?"

或者

alertify.prompt("So " + JSON.stringify(user.Name) + ", what is your greatest ability, STRENGTH, SPEED, or SMARTS?"

希望这能有所帮助！