1 利用js给select添加option并选中该option

<script>
function addOptionToSelect()
{
   var slt=document.getElementById("slt");
   var objOption=document.createElement("OPTION");
   objOption.value='6';
   objOption.text='content';
   slt.add(objOption);
   alert(slt.options.length);
   slt.options[slt.options.length-1].selected='selected';
}

2 JS创建Dom元素

HTML代码

<div class="pc-container">
</div>

JS代码

var container=document.getElementsByClassName('.pc-container')[0];
var div=document.createElement('div');
div.setAttribute('id','example');// div.id = "example";div.className = "slogan";
div.style.width='120px';
container.appendChild(div);

3 JS元素遍历(数组)

参考文章：https://www.cnblogs.com/dailc/p/6103091.html

4 发起ajax异步请求

var frames=window.parent.window.document.getElementById("saveRightMenu");
		var path = "<%= basePath %>";
		$.ajax({
			url:path+"listenUser/insertOrUpdate.do",  
			async:true,
			type:"POST",
			dataType:"json",
			data:{operation:frames.innerHTML,childOperation:this.nextElementSibling.innerHTML},
			success:function(data){
				var result = eval(data);
			    if(result.status==1){
			   		/* console.log("添加/更新成功"); */
			   	}else if(result.status==0){
			   		/* console.log("添加失败"); */
			   	}else{
		    		/* console.log(data); */
		    	}
			}
		})

5 jsp中java变量转js变量

利用jsp的表达式进行赋值

var path = "<%= basePath %>";