<div class="layui-form-item layui-form-text">
   <label class="layui-form-label">资讯内容</label>
   <div class="layui-input-block">
     <textarea name="content" id="demo" placeholder="请输入资讯内容" class="layui-textarea" lay-verify="content"></textarea>
   </div>
</div>

layui.use(['form','layedit'], function() {
    var form = layui.form,
    layer = layui.layer,
    $ = layui.jquery,
    var layedit = layui.layedit;
 
    //创建编辑器
    index = layedit.build('demo',{
      tool:[
        'strong' //加粗
        ,'italic' //斜体
        ,'underline' //下划线
        ,'del' //删除线
        ,'|' //分割线
        ,'left' //左对齐
        ,'center' //居中对齐
        ,'right' //右对齐
        ,'link' //超链接
        ,'unlink' //清除链接
        ,'face' //表情
      ]
    }); //建立编辑器
    
     //自定义验证规则
    form.verify({
      content:function () {
        layedit.sync(index);
      }
    });
})

layedit.setContent(index,$str);