if(!Array.indexOf){ Array.prototype.indexOf = function(obj){ for(var i=0;i<this.length;i++){ if(this[i]==obj) return i; } return -1; } } obviously this does not return a boolean (if…!=-1) but you may want to know the first location of an object in an array so this...
regs.push(new Array("item_2","^[\\s\\S]+$","item_2Span","开户银行不能为空","填写正确",true)); regs.push(new Array("item_3","^[\\s\\S]+$","item_3Span","帐号不能为空","填写正确",true)); //regs.push(new Array("PlantArea","^[\\s\\S]+$","PlantAreaSpan","厂...
console.log(typeof(names));//objectconsole.log(namesinstanceofArray);//trueconsole.log(""instanceofString);//false 不是对象类型console.log(trueinstanceofBoolean);//false 数组对象与方法 Array 对数组的内部支持 Array.concat( ) 连接数组 Array.join( ) 将数组元素连接起来以构建一个字符串 Array.len...
使用contains函数确定指定对象是否是Array对象中的元素。 在Mozilla Firefox 中,如果数组中的项已设置为undefined,则调用item 设置为undefined 的contains函数将返回true。同样的情况下,在所有其他浏览器中,函数都返回false。
string – 如果变量是 String 类型的 object – 如果变量是一种引用类型或 Null 类型的 代码语言:javascript 代码运行次数:0 运行 AI代码解释 functionfoo(){}console.log(typeof8);// numberconsole.log(typeoffoo);// functionconsole.log(typeof("nfit"));// stringconsole.log(typeofjQuery);// undefin...
Array.prototype.contains = function (element) { for (var i = 0; i < this.length; i++) { if (this[i] == element) { return true; } } return false;} 这样就可以直接调用此方法来判断。 var arr = new Array(); if(arr.constains("ddd")){ arr[i] = "dfsdfsd"; } http://bbs....
JavaScript Array every() Theevery()method checks if all array values pass a test. This example checks if all array values are larger than 18: Example constnumbers = [45,4,9,16,25]; letallOver18 =numbers.every(myFunction); functionmyFunction(value, index, array) { ...
看起来很简单,但据我所看到的,使用构造函数,像Array()或者Number()来进行变量转换是常用的做法。始终使用原始数据类型(有时也称为字面量)来转换变量,这种没有任何额外的影响的做法反而效率更高。 var myVar = "3.14159", str = ""+ myVar,// to string ...
JavaScript Array join() Thejoin()method also joins all array elements into a string. It behaves just liketoString(), but in addition you can specify the separator: Example constfruits = ["Banana","Orange","Apple","Mango"]; document.getElementById("demo").innerHTML= fruits.join(" * ")...
charCode; // String.fromCharCode(charCode) 将字符编码转换为字符串 if(!/\d/.test(String.fromCharCode(charCode))){ event.preventDefault(); } }, false) 6.富文本编辑 1.使用contenteditable属性 1.有三个属性: true,false,inherit 2.例子: 2.操作富文本document.execCommand() 三个参数: 要执行的...