how to trigger code on certain elements? but it doesn't affect others












0















I want to display an alert if I select the "b" option, but before that, I'm in the "a" option, not from the "c" option.



<select>

    <option>a</option>

    <option>b</option>

    <option>c</option>

</select>





jquery html







share|improve this question

























  • what JS have you tried thus far?

    – treyBake
    Nov 26 '18 at 10:37











  • $("option).click(function(){alert("show")})";

    – Dio Satria Darma
    Nov 26 '18 at 10:38













  • Do I understand you correctly, you want to only alert when the user clicks on a before clicking on b?

    – Jacob Schneider
    Nov 26 '18 at 10:40











  • with nothing inside the function .. ?

    – treyBake
    Nov 26 '18 at 10:40











  • there is a function

    – Dio Satria Darma
    Nov 26 '18 at 10:42
















0















I want to display an alert if I select the "b" option, but before that, I'm in the "a" option, not from the "c" option.



<select>

    <option>a</option>

    <option>b</option>

    <option>c</option>

</select>





jquery html







share|improve this question

























  • what JS have you tried thus far?

    – treyBake
    Nov 26 '18 at 10:37











  • $("option).click(function(){alert("show")})";

    – Dio Satria Darma
    Nov 26 '18 at 10:38













  • Do I understand you correctly, you want to only alert when the user clicks on a before clicking on b?

    – Jacob Schneider
    Nov 26 '18 at 10:40











  • with nothing inside the function .. ?

    – treyBake
    Nov 26 '18 at 10:40











  • there is a function

    – Dio Satria Darma
    Nov 26 '18 at 10:42














0












0








0








I want to display an alert if I select the "b" option, but before that, I'm in the "a" option, not from the "c" option.



<select>

    <option>a</option>

    <option>b</option>

    <option>c</option>

</select>





jquery html







share|improve this question
















I want to display an alert if I select the "b" option, but before that, I'm in the "a" option, not from the "c" option.



<select>

    <option>a</option>

    <option>b</option>

    <option>c</option>

</select>





jquery html




jquery html






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Nov 26 '18 at 10:47









Nick Parsons

10.2k2926




10.2k2926










asked Nov 26 '18 at 10:32









Dio Satria DarmaDio Satria Darma

74




74













  • what JS have you tried thus far?

    – treyBake
    Nov 26 '18 at 10:37











  • $("option).click(function(){alert("show")})";

    – Dio Satria Darma
    Nov 26 '18 at 10:38













  • Do I understand you correctly, you want to only alert when the user clicks on a before clicking on b?

    – Jacob Schneider
    Nov 26 '18 at 10:40











  • with nothing inside the function .. ?

    – treyBake
    Nov 26 '18 at 10:40











  • there is a function

    – Dio Satria Darma
    Nov 26 '18 at 10:42



















  • what JS have you tried thus far?

    – treyBake
    Nov 26 '18 at 10:37











  • $("option).click(function(){alert("show")})";

    – Dio Satria Darma
    Nov 26 '18 at 10:38













  • Do I understand you correctly, you want to only alert when the user clicks on a before clicking on b?

    – Jacob Schneider
    Nov 26 '18 at 10:40











  • with nothing inside the function .. ?

    – treyBake
    Nov 26 '18 at 10:40











  • there is a function

    – Dio Satria Darma
    Nov 26 '18 at 10:42

















what JS have you tried thus far?

– treyBake
Nov 26 '18 at 10:37





what JS have you tried thus far?

– treyBake
Nov 26 '18 at 10:37













$("option).click(function(){alert("show")})";

– Dio Satria Darma
Nov 26 '18 at 10:38







$("option).click(function(){alert("show")})";

– Dio Satria Darma
Nov 26 '18 at 10:38















Do I understand you correctly, you want to only alert when the user clicks on a before clicking on b?

– Jacob Schneider
Nov 26 '18 at 10:40





Do I understand you correctly, you want to only alert when the user clicks on a before clicking on b?

– Jacob Schneider
Nov 26 '18 at 10:40













with nothing inside the function .. ?

– treyBake
Nov 26 '18 at 10:40





with nothing inside the function .. ?

– treyBake
Nov 26 '18 at 10:40













there is a function

– Dio Satria Darma
Nov 26 '18 at 10:42





there is a function

– Dio Satria Darma
Nov 26 '18 at 10:42












1 Answer
1






active

oldest

votes


















1














You need to create a variable which holds the previous value that you were on. Using this variable you can check whether it was on "a" previously (prev == "a").



See working example below:






let prev = $('select').val();

$('select').change(function() {

  if(prev == 'a' && $(this).val() == 'b') { // Check if the previous value is 'a' and the current value is 'b'

    alert("From a ---> b");

  }

  prev = $(this).val();

});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<select>

  <option>a</option>

  <option>b</option>

  <option>c</option>

</select>








share|improve this answer


























  • you don't necessarily need to declare a variable - you can just get value on click, if value is b do action - unless I'm misunderstanding the question

    – treyBake
    Nov 26 '18 at 10:39











  • I believe that's the case, to only trigger the event if a previous has occured

    – Jacob Schneider
    Nov 26 '18 at 10:40











  • @treyBake I think OP wants it so that if you go from "a" then go to "b" it will display an alert. So if you went from "c" to "b" it wouldn't do anything

    – Nick Parsons
    Nov 26 '18 at 10:40











  • @NickParsons hmm I feel like the question is worded too loosely ... maybe I'm just not seeing it as clearly as others ... but hard to tell for me :/

    – treyBake
    Nov 26 '18 at 10:41











  • can you simplify the coding? like $ ("option"). click (function () {alert ("a-> b")});

    – Dio Satria Darma
    Nov 26 '18 at 10:44












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1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









1














You need to create a variable which holds the previous value that you were on. Using this variable you can check whether it was on "a" previously (prev == "a").



See working example below:






let prev = $('select').val();

$('select').change(function() {

  if(prev == 'a' && $(this).val() == 'b') { // Check if the previous value is 'a' and the current value is 'b'

    alert("From a ---> b");

  }

  prev = $(this).val();

});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<select>

  <option>a</option>

  <option>b</option>

  <option>c</option>

</select>








share|improve this answer


























  • you don't necessarily need to declare a variable - you can just get value on click, if value is b do action - unless I'm misunderstanding the question

    – treyBake
    Nov 26 '18 at 10:39











  • I believe that's the case, to only trigger the event if a previous has occured

    – Jacob Schneider
    Nov 26 '18 at 10:40











  • @treyBake I think OP wants it so that if you go from "a" then go to "b" it will display an alert. So if you went from "c" to "b" it wouldn't do anything

    – Nick Parsons
    Nov 26 '18 at 10:40











  • @NickParsons hmm I feel like the question is worded too loosely ... maybe I'm just not seeing it as clearly as others ... but hard to tell for me :/

    – treyBake
    Nov 26 '18 at 10:41











  • can you simplify the coding? like $ ("option"). click (function () {alert ("a-> b")});

    – Dio Satria Darma
    Nov 26 '18 at 10:44
















1














You need to create a variable which holds the previous value that you were on. Using this variable you can check whether it was on "a" previously (prev == "a").



See working example below:






let prev = $('select').val();

$('select').change(function() {

  if(prev == 'a' && $(this).val() == 'b') { // Check if the previous value is 'a' and the current value is 'b'

    alert("From a ---> b");

  }

  prev = $(this).val();

});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<select>

  <option>a</option>

  <option>b</option>

  <option>c</option>

</select>








share|improve this answer


























  • you don't necessarily need to declare a variable - you can just get value on click, if value is b do action - unless I'm misunderstanding the question

    – treyBake
    Nov 26 '18 at 10:39











  • I believe that's the case, to only trigger the event if a previous has occured

    – Jacob Schneider
    Nov 26 '18 at 10:40











  • @treyBake I think OP wants it so that if you go from "a" then go to "b" it will display an alert. So if you went from "c" to "b" it wouldn't do anything

    – Nick Parsons
    Nov 26 '18 at 10:40











  • @NickParsons hmm I feel like the question is worded too loosely ... maybe I'm just not seeing it as clearly as others ... but hard to tell for me :/

    – treyBake
    Nov 26 '18 at 10:41











  • can you simplify the coding? like $ ("option"). click (function () {alert ("a-> b")});

    – Dio Satria Darma
    Nov 26 '18 at 10:44














1












1








1







You need to create a variable which holds the previous value that you were on. Using this variable you can check whether it was on "a" previously (prev == "a").



See working example below:






let prev = $('select').val();

$('select').change(function() {

  if(prev == 'a' && $(this).val() == 'b') { // Check if the previous value is 'a' and the current value is 'b'

    alert("From a ---> b");

  }

  prev = $(this).val();

});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<select>

  <option>a</option>

  <option>b</option>

  <option>c</option>

</select>








share|improve this answer















You need to create a variable which holds the previous value that you were on. Using this variable you can check whether it was on "a" previously (prev == "a").



See working example below:






let prev = $('select').val();

$('select').change(function() {

  if(prev == 'a' && $(this).val() == 'b') { // Check if the previous value is 'a' and the current value is 'b'

    alert("From a ---> b");

  }

  prev = $(this).val();

});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<select>

  <option>a</option>

  <option>b</option>

  <option>c</option>

</select>








let prev = $('select').val();

$('select').change(function() {

  if(prev == 'a' && $(this).val() == 'b') { // Check if the previous value is 'a' and the current value is 'b'

    alert("From a ---> b");

  }

  prev = $(this).val();

});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<select>

  <option>a</option>

  <option>b</option>

  <option>c</option>

</select>





let prev = $('select').val();

$('select').change(function() {

  if(prev == 'a' && $(this).val() == 'b') { // Check if the previous value is 'a' and the current value is 'b'

    alert("From a ---> b");

  }

  prev = $(this).val();

});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<select>

  <option>a</option>

  <option>b</option>

  <option>c</option>

</select>






share|improve this answer














share|improve this answer



share|improve this answer








edited Nov 26 '18 at 10:45

























answered Nov 26 '18 at 10:37









Nick ParsonsNick Parsons

10.2k2926




10.2k2926













  • you don't necessarily need to declare a variable - you can just get value on click, if value is b do action - unless I'm misunderstanding the question

    – treyBake
    Nov 26 '18 at 10:39











  • I believe that's the case, to only trigger the event if a previous has occured

    – Jacob Schneider
    Nov 26 '18 at 10:40











  • @treyBake I think OP wants it so that if you go from "a" then go to "b" it will display an alert. So if you went from "c" to "b" it wouldn't do anything

    – Nick Parsons
    Nov 26 '18 at 10:40











  • @NickParsons hmm I feel like the question is worded too loosely ... maybe I'm just not seeing it as clearly as others ... but hard to tell for me :/

    – treyBake
    Nov 26 '18 at 10:41











  • can you simplify the coding? like $ ("option"). click (function () {alert ("a-> b")});

    – Dio Satria Darma
    Nov 26 '18 at 10:44



















  • you don't necessarily need to declare a variable - you can just get value on click, if value is b do action - unless I'm misunderstanding the question

    – treyBake
    Nov 26 '18 at 10:39











  • I believe that's the case, to only trigger the event if a previous has occured

    – Jacob Schneider
    Nov 26 '18 at 10:40











  • @treyBake I think OP wants it so that if you go from "a" then go to "b" it will display an alert. So if you went from "c" to "b" it wouldn't do anything

    – Nick Parsons
    Nov 26 '18 at 10:40











  • @NickParsons hmm I feel like the question is worded too loosely ... maybe I'm just not seeing it as clearly as others ... but hard to tell for me :/

    – treyBake
    Nov 26 '18 at 10:41











  • can you simplify the coding? like $ ("option"). click (function () {alert ("a-> b")});

    – Dio Satria Darma
    Nov 26 '18 at 10:44

















you don't necessarily need to declare a variable - you can just get value on click, if value is b do action - unless I'm misunderstanding the question

– treyBake
Nov 26 '18 at 10:39





you don't necessarily need to declare a variable - you can just get value on click, if value is b do action - unless I'm misunderstanding the question

– treyBake
Nov 26 '18 at 10:39













I believe that's the case, to only trigger the event if a previous has occured

– Jacob Schneider
Nov 26 '18 at 10:40





I believe that's the case, to only trigger the event if a previous has occured

– Jacob Schneider
Nov 26 '18 at 10:40













@treyBake I think OP wants it so that if you go from "a" then go to "b" it will display an alert. So if you went from "c" to "b" it wouldn't do anything

– Nick Parsons
Nov 26 '18 at 10:40





@treyBake I think OP wants it so that if you go from "a" then go to "b" it will display an alert. So if you went from "c" to "b" it wouldn't do anything

– Nick Parsons
Nov 26 '18 at 10:40













@NickParsons hmm I feel like the question is worded too loosely ... maybe I'm just not seeing it as clearly as others ... but hard to tell for me :/

– treyBake
Nov 26 '18 at 10:41





@NickParsons hmm I feel like the question is worded too loosely ... maybe I'm just not seeing it as clearly as others ... but hard to tell for me :/

– treyBake
Nov 26 '18 at 10:41













can you simplify the coding? like $ ("option"). click (function () {alert ("a-> b")});

– Dio Satria Darma
Nov 26 '18 at 10:44





can you simplify the coding? like $ ("option"). click (function () {alert ("a-> b")});

– Dio Satria Darma
Nov 26 '18 at 10:44




















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