Question

我有这样的代码：

<html>
<head>
    <script language="javascript">
        window.onload = function() {
            var wordlist = [ "A", "BB", "CCC", "DDDD" ];

            for(i = 0; i < 26; i++) {
                var x = document.createElement("INPUT");
                x.setAttribute("type", "button");
                x.setAttribute("value", String.fromCharCode(i + 65));
                x.setAttribute("id", String.fromCharCode(i + 65));
                x.setAttribute("onclick", "isTOF(this.id, wordlist[3])");
                document.body.appendChild(x);
            }
        }

        function isTOF(v, word) {
            console.log(word);
        }
    </script>
</head>
<body>
</body>
</html>

我认为console.log(word)会给我看“ DDDD”，但它是这样说的：

未定义单词列表

我如何使其运行？

Answer 1

参数字符串未正确连接，应为：

x.setAttribute("onclick", "isTOF(this.id, '" + wordlist[3] + "')")

尽管我更喜欢使用Template Literals来允许嵌入表达式：

<html>
<head>
    <script language="javascript">
        window.onload = function() {
            var wordlist = [ "A", "BB", "CCC", "DDDD" ];

            for(i = 0; i < 26; i++) {
                var x = document.createElement("INPUT");
                x.setAttribute("type", "button");
                x.setAttribute("value", String.fromCharCode(i + 65));
                x.setAttribute("id", String.fromCharCode(i + 65));
                x.setAttribute("onclick", `isTOF(this.id, '${wordlist[3]}')`);
                document.body.appendChild(x);
            }
        }

        function isTOF(v, word) {
            console.log(word);
        }
    </script>
</head>
<body>
</body>
</html>

为什么在同一函数中未定义var？

1 个答案: