why does the first code work and the second doesn't work?












-1















when I put div.main as a separated condition the code doesn't work



<div class="user-panel main"> 
<input type="text" name="login">
</div>




document.querySelector("div.user-panel.main input[name='login']").style.backgroundColor = "red"; // this code works
document.querySelector("div.user-panel div.main input[name='login']").style.backgroundColor = "red"; // this code doesn't work









share|improve this question























  • remove the div.main. So change your second selector to document.querySelector("div.user-panel.main input[name='login']")

    – Nick Parsons
    Nov 25 '18 at 3:30
















-1















when I put div.main as a separated condition the code doesn't work



<div class="user-panel main"> 
<input type="text" name="login">
</div>




document.querySelector("div.user-panel.main input[name='login']").style.backgroundColor = "red"; // this code works
document.querySelector("div.user-panel div.main input[name='login']").style.backgroundColor = "red"; // this code doesn't work









share|improve this question























  • remove the div.main. So change your second selector to document.querySelector("div.user-panel.main input[name='login']")

    – Nick Parsons
    Nov 25 '18 at 3:30














-1












-1








-1








when I put div.main as a separated condition the code doesn't work



<div class="user-panel main"> 
<input type="text" name="login">
</div>




document.querySelector("div.user-panel.main input[name='login']").style.backgroundColor = "red"; // this code works
document.querySelector("div.user-panel div.main input[name='login']").style.backgroundColor = "red"; // this code doesn't work









share|improve this question














when I put div.main as a separated condition the code doesn't work



<div class="user-panel main"> 
<input type="text" name="login">
</div>




document.querySelector("div.user-panel.main input[name='login']").style.backgroundColor = "red"; // this code works
document.querySelector("div.user-panel div.main input[name='login']").style.backgroundColor = "red"; // this code doesn't work






javascript dom jsdom






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asked Nov 25 '18 at 3:27









Abdullah MorsyAbdullah Morsy

62




62













  • remove the div.main. So change your second selector to document.querySelector("div.user-panel.main input[name='login']")

    – Nick Parsons
    Nov 25 '18 at 3:30



















  • remove the div.main. So change your second selector to document.querySelector("div.user-panel.main input[name='login']")

    – Nick Parsons
    Nov 25 '18 at 3:30

















remove the div.main. So change your second selector to document.querySelector("div.user-panel.main input[name='login']")

– Nick Parsons
Nov 25 '18 at 3:30





remove the div.main. So change your second selector to document.querySelector("div.user-panel.main input[name='login']")

– Nick Parsons
Nov 25 '18 at 3:30












2 Answers
2






active

oldest

votes


















2














When your selectors are combined with a space - a descendant combinator - it's called a descendant selector. So



document.querySelector("div.user-panel  div.main input[name='login']")


is looking for a input[name='login'] inside a div.main inside a div.user-panel.



Since in your html it's just a single div with 2 classes, this selector doesn't find anything.



It would work, however, if your html was looking like this:



<div class="user-panel">
<div class="main">
<input type="text" name="login">
</div>
</div>





share|improve this answer

































    0














    A space in a query selector denotes one element is inside another. The second line is looking for input[name='login'] contained in div.main, which is contained within another div (div.user-panel).






    share|improve this answer























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      2 Answers
      2






      active

      oldest

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      2 Answers
      2






      active

      oldest

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      active

      oldest

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      active

      oldest

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      2














      When your selectors are combined with a space - a descendant combinator - it's called a descendant selector. So



      document.querySelector("div.user-panel  div.main input[name='login']")


      is looking for a input[name='login'] inside a div.main inside a div.user-panel.



      Since in your html it's just a single div with 2 classes, this selector doesn't find anything.



      It would work, however, if your html was looking like this:



      <div class="user-panel">
      <div class="main">
      <input type="text" name="login">
      </div>
      </div>





      share|improve this answer






























        2














        When your selectors are combined with a space - a descendant combinator - it's called a descendant selector. So



        document.querySelector("div.user-panel  div.main input[name='login']")


        is looking for a input[name='login'] inside a div.main inside a div.user-panel.



        Since in your html it's just a single div with 2 classes, this selector doesn't find anything.



        It would work, however, if your html was looking like this:



        <div class="user-panel">
        <div class="main">
        <input type="text" name="login">
        </div>
        </div>





        share|improve this answer




























          2












          2








          2







          When your selectors are combined with a space - a descendant combinator - it's called a descendant selector. So



          document.querySelector("div.user-panel  div.main input[name='login']")


          is looking for a input[name='login'] inside a div.main inside a div.user-panel.



          Since in your html it's just a single div with 2 classes, this selector doesn't find anything.



          It would work, however, if your html was looking like this:



          <div class="user-panel">
          <div class="main">
          <input type="text" name="login">
          </div>
          </div>





          share|improve this answer















          When your selectors are combined with a space - a descendant combinator - it's called a descendant selector. So



          document.querySelector("div.user-panel  div.main input[name='login']")


          is looking for a input[name='login'] inside a div.main inside a div.user-panel.



          Since in your html it's just a single div with 2 classes, this selector doesn't find anything.



          It would work, however, if your html was looking like this:



          <div class="user-panel">
          <div class="main">
          <input type="text" name="login">
          </div>
          </div>






          share|improve this answer














          share|improve this answer



          share|improve this answer








          edited Nov 25 '18 at 3:51

























          answered Nov 25 '18 at 3:34









          shkapershkaper

          1,3511814




          1,3511814

























              0














              A space in a query selector denotes one element is inside another. The second line is looking for input[name='login'] contained in div.main, which is contained within another div (div.user-panel).






              share|improve this answer




























                0














                A space in a query selector denotes one element is inside another. The second line is looking for input[name='login'] contained in div.main, which is contained within another div (div.user-panel).






                share|improve this answer


























                  0












                  0








                  0







                  A space in a query selector denotes one element is inside another. The second line is looking for input[name='login'] contained in div.main, which is contained within another div (div.user-panel).






                  share|improve this answer













                  A space in a query selector denotes one element is inside another. The second line is looking for input[name='login'] contained in div.main, which is contained within another div (div.user-panel).







                  share|improve this answer












                  share|improve this answer



                  share|improve this answer










                  answered Nov 25 '18 at 3:40









                  tshimkustshimkus

                  817920




                  817920






























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