2015714

array: var arr = new Array(1, 2, 3); var arr1 = new Array("a", "b", "c"); var arr2 = new Array(true, true, true); //往数组的末尾添加值,可以是一个或者多个值,中间通过,分隔; alert(arr.push(4, 5)); //连接数组元素,中间有分隔符; var str = arr.join(" ");alert(str); //颠倒数组的顺序,是操作本身; alert(arr.reverse()); //增加删除元素 var arr = new Array(6); arr[0] = "George"; arr[1] = "John"; arr[2] = "Thomas"; arr[3] = "James"; arr[4] = "Adrew"; arr[5] = "Martin"; arr.splice(0,1, "test"); alert(arr);连接两个或多个数组 alert(arr.concat(arr1, arr2));

 

isNaN:

<input id="txt" type="text"/><input id="btn" type="button" value="点我"/>

<script type="text/javascript"> var txt = document.getElementById("txt"); var btn = document.getElementById("btn"); btn.onclick = function () { if(!isNaN(txt.value)) { var num = parseInt(txt.value); alert(num * num); } else { alert("请输入合法的数字!!"); }

math

//最大值 var max = Math.max(1, 2, 3);// alert(max); //最小值 var min = Math.min(1, 2, 3);// alert(min);

// var r = Math.random();

var r = parseInt(Math.random() * 1000); alert(r);

var r1 = Math.round(4.1); alert(r1);

 

 

输出日期：

var today = new Date(); var year = today.getFullYear(); var month = today.getMonth(); var day = today.getDate(); var hours = today.getHours(); var mins = today.getMinutes(); var s = today.getSeconds(); var str = year + "年" + (month + 1) + "月" + day + "日" + hours; alert(str);

转载于:https://www.cnblogs.com/lily-w/p/4646815.html