tit1819202204
/
js.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

</head>
<script>
    <!--    九九乘法表-->
    for (let i = 1; i <= 9; i++) {

        for (let j = 1; j <= i; j++) {
            document.write("" + i + "*" + j + "" + "=" + i * j + " ")

        }
        document.write("</br>")
    }
    var p = 0;

    while (true) {
        p++;
        if (p == 3) {
            document.write(p)
            document.write("</br>")
            break
        }
    }

    function f() {
        alert("哇哦")
    }

    function f2() {
        var num = document.getElementById("user").value;
        let reg = /^[\u4e00-\u9fa5]*$/;
        let b = reg.test(num);
        if (b) {
            var w= document.getElementById("s")
            w.innerText=" "
        } else {
          var w= document.getElementById("s")
            w.style.color="red"
            w.innerText="用户输入不合法"

        }

    }

    function f3(v) {
        alert("值变化了" + v)
    }

</script>
<body>
<!--双击事件-->
<button ondblclick="f()">电脑</button>
<!--失去焦点事件-->
<input type="text" id="user" onblur="f2()">
<select onchange="f3(value)">
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
</select>
<span type="text" id="s" ></span>
<!--值得变化触发的事件-->

</body>
</html>