Question

当用户选择“生成”按钮并在文本字段中设置值时，我需要生成一个随机数。如何在“randomNum”文本字段中设置“输出变量”。

HTML code：

<form action="submit.jsp" method= "post" name="privateKey">
            Random String: <input type="text" name="randomNum" onkeyleave="generate()">
            <input type="button" name="generate" value="Generate!" >

</form>

使用Javascript：

     function generate() {
           char[] chars = "abcdefghijklmnopqrstuvwxyz".toCharArray();
           StringBuilder sb = new StringBuilder();
           Random random = new Random();
           for (int i = 0; i < 20; i++) {
               char c = chars[random.nextInt(chars.length)];
               sb.append(c);
           }
           String output = sb.toString();
        }

Answer 1

试试这个

HTML：

<form action="submit.jsp" method= "post" name="privateKey">
            Random String: <input type="text" name="randomNum" id="demo" onkeyleave="generate()">
            <input type="button" name="generate" value="Generate!" >

</form>

JavaScript的：

function generate() {
           char[] chars = "abcdefghijklmnopqrstuvwxyz".toCharArray();
           StringBuilder sb = new StringBuilder();
           Random random = new Random();
           for (int i = 0; i < 20; i++) {
               char c = chars[random.nextInt(chars.length)];
               sb.append(c);
           }
            document.getElementById("demo").value = sb.toString();
        }

Answer 2

为输入文本设置ID：

 <input id="randomtxt" type="text" name="randomNum" onkeyleave="generate()">

应该更改函数的最后一行：

 document.getElementById("randomtxt").value= sb.toString();

如何在Javascript中设置JSP中textfield的值

2 个答案: