微信调用原生图片查看功能

function addLoadEvent(func){    let oldonload=window.onload;       if(typeof window.onload!="function"){          window.onload=func();       }else{           window.onload=()=>{              oldonload();              func();           }      }  }  let imgs=new Array();  let ImgUrl="";  function getPicInfo(){      let imgObj=document.getElementsByTagName('img');     for(let i=0; i<imgObj.length; i++){          imgs.push(imgObj[i].src);           imgObj[i].onclick=function(){              ImgUrl = this.src;               WeixinJSBridge.invoke("imagePreview",{                  "urls":imgs,                  "current":ImgUrl                  })          }      }  }  addLoadEvent(getPicInfo);

在 window.onload后 直接调用