code: function initDomSelecter(){
          divDomSelector = document.createElement("div");
          divDomSelector.id = 'uirecorder-selecter-mask';
          divDomSelector.className = 'uirecorder';
          divDomSelector.innerHTML = '<style>#uirecorder-selecter-mask{display:none;background:rgba(151, 232, 81,0.5);position:fixed;z-index:2147483647;}</style>';
          divDomSelector.addEventListener('click', function(event){
              event.stopPropagation();
              event.preventDefault();
              endDomSelector(event);
          });
          document.body.appendChild(divDomSelector);
      }
docs: 初始化选择器