making a gallery with display none

i'm new in js, im trying to make a hide/show img when i press a button... but it's not working can someone help me? thanks alot

function nextImgRight(){

var img1 = document.querySelector("#img01")
var img2 = document.querySelector("#img02")
var img3 = document.querySelector("#img03")
var img4 = document.querySelector("#img04")
var img5 = document.querySelector("#img05")
var img6 = document.querySelector("#img06")

      if(img1.style.display="block"){
      img1.style.display="none";
      img2.style.display="block";
      img3.style.display="none";
      img4.style.display="none";
      img5.style.display="none";
      img6.style.display="none";}


      else if(img2.style.display="block"){
      img1.style.display="none";
      img2.style.display="none";
      img3.style.display="block";
      img4.style.display="none";
      img5.style.display="none";
      img6.style.display="none";
      }


}