数组操作方法concat，slice和splice

// 拼接数组var colors=[1,2,1];var colors1=colors.concat(1,[3,1,11]);alert(colors);      //1,2,1alert(colors1);     //1,2,1,1,3,1,11alert(colors.length);   //3alert(colors1.length);  //7// slice(a)从a开始到数组结束，slice(a,b)从a开始到b之前var arr1=["cjx","jlx","xqr","why","lxy","lxf"];alert(arr1.slice(1));       //jlx,xqr,why,lxy,lxfalert(arr1.slice(1,3))      //jlx,xqr// splice(a,b,c) a起始位置，b删除的项数，c插入的内容var arr2=["cjx","jlx","xqr","why","lxy","lxf"];// 删除var remove=arr2.splice(0,1);console.log(arr2);  //jlx,xqr,why,lxy,lxfconsole.log(remove);    //cjx// 插入var remove1=arr2.splice(0,0,12);console.log(arr2);      //12,jlx,xqr,why,lxy,lxfconsole.log(remove1);   //[]空数组// 替换var remove2=arr2.splice(1,1,"qq")console.log(arr2)       //12,qq,xqr,why,lxy,lxfconsole.log(remove2);   //jlx