JAVASCRIPT 的新问题，涉及 IF 语句和多个值

Question

我有一个页面，该页面是一个表单，可以有 33 个问题或 28 个问题，具体取决于用户选择的表单。该表单根据用户的选择来计算用户的分数。当它只是一种表单时，表单工作正常，但我需要它以不同的方式工作，因为如果用户选择它，某些问题会导致分数下降而不是上升。这是我正在使用的 JAVASCRIPT。之前的代码只有一个 if 语句 qtn_nbr <=16。我添加了新的 var form_nm，它告诉我表格是否需要在 16 或 18 个问题处进行减法。然而，下面的代码仅识别 18 的第一个 if 语句，但是当我切换到 16 的表单时，即使 form_nm 的值现在是 16，它也不会转到 else if 。有人可以看看我的语法，让我知道我是否遗漏了某些内容，或者他们是否有更好的逻辑让我在这两个值之间切换？任何帮助将不胜感激。

function valuechanged(inval, totalqtns)

{

    //alert(inval.name);

    //alert(inval.value);

    var val = inval.value;

    var str = inval.name;

    var qtn_nbr = String(str).substring(4);//get the number of the question

    

    var formnm = document.getElementById(formname); //get question number

    //alert(qtn_nbr);

    var txt1 = 'pos_pt_' + qtn_nbr;

    //alert(document.getElementById(txt1).value);

    var txt2 = 'pt_' + qtn_nbr;

    var txt3 = 'qtn_' + qtn_nbr + '_comm';

    var txt4 ='comm_' + qtn_nbr;

    //alert('here');//current display of here when clicking on any point value!

    document.getElementById(txt2).value= 0;

    //alert(document.getElementById(txt2).value);

    if (formnm = 18 && qtn_nbr <= 18)

    {

        

            if (val == 'yes')

                {

                document.getElementById(txt2).value = document.getElementById(txt1).value;

                //document.getElementById(txt3).disabled = true;

                document.getElementById(txt3).value='';

                document.getElementById(txt4).value='';

                }

            else if (val == 'half')

                {

                document.getElementById(txt2).value = parseInt(document.getElementById(txt1).value)/2;

                //document.getElementById(txt3).disabled = false;

                }

            else

                {

                document.getElementById(txt2).value = 0;

                //document.getElementById(txt3).disabled = false;

                }

        

    }

Answer 1

我明白了，谢谢你的帮助。如果我在 if 语句中使用值，而不是设置变量，那么它会与 == 一起使用。&nbsp; &nbsp; if (document.getElementById('formname').value == 18 && qtn_nbr <= 18)&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (val == 'yes')&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; document.getElementById(txt2).value = document.getElementById(txt1).value;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; //document.getElementById(txt3).disabled = true;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; document.getElementById(txt3).value='';&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; document.getElementById(txt4).value='';&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; else if (val == 'half')&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; document.getElementById(txt2).value = parseInt(document.getElementById(txt1).value)/2;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; //document.getElementById(txt3).disabled = false;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; else&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; document.getElementById(txt2).value = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; //document.getElementById(txt3).disabled = false;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; }else if (document.getElementById('formname').value == 16 && qtn_nbr <= 16)&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; if (val == 'yes')&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; document.getElementById(txt2).value = document.getElementById(txt1).value;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; //document.getElementById(txt3).disabled = true;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; document.getElementById(txt3).value='';&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; document.getElementById(txt4).value='';&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; else if (val == 'half')&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; document.getElementById(txt2).value = parseInt(document.getElementById(txt1).value)/2;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; //document.getElementById(txt3).disabled = false;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; else&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; document.getElementById(txt2).value = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; //document.getElementById(txt3).disabled = false;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp;&nbsp;&nbsp; &nbsp; }&nbsp; &nbsp;