javascript - How I change a value of hidden file in the file HTML.Twig -

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• how change value of hidden file according radio selected 3 answers

i have in file html.twig:

1: one hidden filed should take 3 values according radio selected, 1 database , 2 others value 10.

<input type="hidden" name="lt_filed" value="{{ price.getlt }}" or "10" or "10"> 

2: 3 radio box

<input id="spa-price" name="price" class="w3-radio" onchange='valuelt();' value="spare {{ price.getspareprice }}" type="radio"> <input id="rep-price" name="price" class="w3-radio" onchange='valuelt();' value="repair{{ price.getrepairprice }}" type="radio"> <input id="tes-price" name="price" class="w3-radio" onchange='valuelt();' value="test {{ price.gettestprice }}" type="radio"> 

3: did block javascript in same file html.twig, created function values of each radio, following:

{% block javasc %} <script>         function valuelt(){           var spare= document.getelementbyid('spa-price');           var repair= document.getelementbyid('rep-price');           var test= document.getelementbyid('tes-price');            var hidden_filed =   document.getelementsbyname("lt_filed");             if (repair.checked){ // should take value 10               alert("repair checked");               hidden_filed.value = 10;            } else if (test.checked){ // should take value 10              alert("test checked");              hidden_filed.value = 10;            } else {              alert("spare checked"); // should take value database              hidden_filed.value = {{ price.getlt }};// here can't recovred   value database              }         }      </script> {% endblock %} 

can tell me how can value {{ price.getlt }} twig or javascript ?

thank you.

well, document.getelementsbyname(param) function doesn't return element instance, returns array of elements. should pick first element :

{% block javasc %} <script>         function valuelt(){           var spare= document.getelementbyid('spa-price');           var repair= document.getelementbyid('rep-price');           var test= document.getelementbyid('tes-price');            var hidden_filed =   document.getelementsbyname("lt_filed")[0]; // change line            if (repair.checked){ // should take value 10               alert("repair checked");               hidden_filed.value = 10;            } else if (test.checked){ // should take value 10              alert("test checked");              hidden_filed.value = 10;            } else {              alert("spare checked"); // should take value database              hidden_filed.value = {{ price.getlt }};// here can't recovred   value database              }         }      </script> {% endblock %}