I've looked through the prior questions but do not see an answer that I can understand (they are all more complicated than mine).
I'm bootstrapping some javascript using old manuals and my experiences using a scripting language back 15 years ago.
By modifying a tutorial file I have this code and it works fine
var oemdc1 = parseInt(document.getElementById("vehicle_oem_draw").value);
var oemdc2 = parseInt(document.getElementById("vehicle_added_draw").value);
var oemdc3 = parseInt(document.getElementById("new_vehicle_draw").value);
var oemdc4 = parseInt(document.getElementById("include_prism_draw").value);
var total_current_draw = document.getElementById("total_hourly_current_draw");
total_current_draw.value = oemdc1 + oemdc2 + oemdc3
But I need to add this code so that if the user clicks a radio button (include_prism_draw) they get a different total.
if (oemdc4 == 1)
total_current_draw.value = oemdc1 + oemdc2 + oemdc3 + prism_cd;
else
total_current_draw.value = oemdc1 + oemdc2 + oemdc3;
But I get the added value (prism_cd) in my calculation regardless of the radio button values (a "1" or a "0"). Even if neither button is clicked I still get the added value.
So I think I need some braces or parentheses or something.
I have the var prism_cd declared at the top of the doc and it is inserted into a results field so it is working in that sense.
Any help is much appreciated.
(Okay, found the edit link, they should make it more prominent).
I cut/pasted the code from #Adam and still get the prism_cd regardless of the state of the buttons. (prism_cd is a number I set as a var and it shows up accurately but even when I don't want it.)
the button code is below. Maybe there is a simple mistake
Include PRISM 1.5 mA current draw in calculation?
<input type="radio" name="include_prism_draw" id="include_prism_draw" value="1" /> Yes
<input type="radio" name="include_prism_draw" id="include_prism_draw" value="0" /> No
To answer the other question about the vars, they are from popups the user manipulates, the script adds the values from the popups and does so accurately until I add the yes/no code with the buttons.
If the user wants to add the prism current draw (prism_cd) they click yes and it is to be added but as I say it is getting added whenever the code is in the script. At this point I do not have either button set to be checked.
The rest of script works accurately as I can test with the spreadsheet I am porting it from.
I still have more things to work through but they are mostly based on this type of "if/else set a var" logic so once I get this working hopefully I should be good to go.
I very much appreciate the replies.
M./
I'm not certain what your problem is. But, the best practice for if..else syntax is to put both blocks in braces.
var oemdc1 = parseInt(document.getElementById("vehicle_oem_draw").value);
var oemdc2 = parseInt(document.getElementById("vehicle_added_draw").value);
var oemdc3 = parseInt(document.getElementById("new_vehicle_draw").value);
var oemdc4 = parseInt(document.getElementById("include_prism_draw").value);
var total_current_draw = document.getElementById("total_hourly_current_draw");
if (oemdc4 === 1){
total_current_draw.value = oemdc1 + oemdc2 + oemdc3 + prism_cd;
} else {
total_current_draw.value = oemdc1 + oemdc2 + oemdc3;
}
Look at this question: Get Radio Button Value with Javascript
You cannot get the value of a number of associated radio-buttons by just doing
document.getElementById(ID).value;
also look at this question, why you should not give the same id to multiple HTML elements: Why is it a bad thing to have multiple HTML elements with the same id attribute?
Now a possible simple solution for you problem (according to solution from first link):
You could write a function, which returns the value of your two radio-buttons:
function getPrismDrawValue()
{
// predefined result, if no radio button is checked.
// in this case result will be 0 -> "No"
var result = 0;
// get a list of all HTML-elements with the name 'include_prism_draw'
var radios = document.getElementsByName('include_prism_draw');
// loop through all this elements and check if one of them is checked
for (var i = 0; i < radios.length; i++)
{
if (radios[i].checked)
{
// get the value of the checked radio button
result = parseInt(radios[i].value);
// only one radio can be logically checked, don't check the rest
break;
}
}
return result;
}
Now your variable oemdc4 should be declared like this:
var oemdc4 = getPrismDrawValue();
EDIT to answer new question:
now your problem is here:
var oemdc4 = parseInt(document.getElementById("prism_draw").value);
if you pass 1.5 to parseInt()-function it will return 1.
use function parseFloat() instead to get your expected result.
var oemdc4 = parseFloat(document.getElementById("prism_draw").value);
I realize this might be a silly question, and I apologize in advance, but I was hoping there'd be an easier way to do this.
For example if I set the text of a div like so:
divOne.textContent = someVariable + "/5";
and I have about 60 divs that are like cells in one div container. Is there any way I can update the text values without manually calling it each time? The problem isn't when they change a cell one by one, it's when they hit the reset button. Is there a way to do it without writing 60 lines of text? Would the only solution be something like:
divOne.updateText = function() { this.textContent = someVariable + "/5"; }
and would that even be an ok solution? Creating 60 extra parameters each with a function overkill?
Any information on this subject is greatly appreciated, thanks in advance.
Edit:
The reason why I didn't use the for loop to begin with is because each cell has a different max value, aka the 5 from someVariable + "/5" . I was asking after your comment though if it'd be better to just do something like this instead though:
someDiv[0].max = 5
someDiv[i].textContent = someDiv[i].points + "/" + someDiv[i].max;
//the above would be inside a for loop.
over doing the .updateText = function
Based on your comment, you can just loop through your array using a for loop.
var someDiv = [];
// Fill array with elements
for (var i = 0, len = someDiv.length; i < len; i++) {
someDiv[i].textContent = someDiv[i].points + "/" + someDiv[i].max;
}
I have a series of arrays that contain words I want to use as text in various HTML divs (there are about 35 of these, I included only a few for brevity).
var bodyplan = ['Anguilliform', 'Compressiform', 'Depressiform', 'Filiform', 'Fusiform', 'Globiform', 'Sagittiform', 'Taeniform'];
var mouthposition = ["Inferior", "Jawless", "Subterminal", "Superior", "Terminal"];
var barbels = ['1', '2', '4 or more'];
var caudalshape = ['Continuous', 'Emarginate', 'Forked', 'Lunate', 'Rounded', 'Truncate'];
I have a switch function that is supposed to change the text based on user selections:
switch(n){
case 1:
changelabels(bodyplan, 8);
break;
case 2:
changelabels(mouthposition, 5);
break;
case 3:
changelabels(barbels, 3);
break;
case 4:
changelabels(caudalshape, 6);
break;
case 5:
changelabels(dorsalspines, 8);
break;
default:
alert("handquestsel error")}};
Finally, I have the function which I would like to make the changes (except it doesn't):
function changelabels(opt1,opt2){
var i = opt2;
var im = opt2 - 1;
var c = 1;
var index = 0;
while (i>=c){
var oldlbl = document.getElementById("rb" + c + "lbl");
var newlbla = opt1.slice(im,i);
var newlblb = opt1.toString();
oldlbl.innerHTML = newlblb;
c = c + 1
index = index + 1
}};
I know the code for my function is just plain wrong at this point, but I have altered it so many times that I'm not sure what's going on anymore. At one point I did have the function able to change the text, but it did so incorrectly (it parsed the name of the array, not extracted a value from the array as I wished). Please help. I know I am overlooking some fundamental concepts here, but am not sure which ones. I've lost count of the hours I've spent trying to figure this out. It's seems like it should be so simple, yet in all my chaotic attempts to make it work, I have yet to stumble on an answer.
EDIT: I want my switch statement to call the function and pass to the function, the appropriate array from which to pull the labels from. The purpose of the app is to help a user learn to identify fish. When the user makes selections on the page, a series of pictures will be shown for various character states with an accompanying label describing the state. For example, when the user selects Mouth Position a series of divs will show the different mouth positions that fish have and have a label below the picture to tell the user what that certain character state is called. I can get the pictures to change just fine, but I am having a hell of a time with the labels.
Why not just something along the lines of:
document.getElementById("bodyplan_label").innerHTML = bodyplan[bodyplan_index];
You seem trying to put everything in really abstract data structures, I see no reason to. Just keep it simple.
Also bodyplan has only 8 elements, so bodyplan[8] will give you an out of bounds exception because arrays start at 0 as is common in all modern programming languages.
If I'm reading your requirement and code correctly, in your switch statement you are passing both a reference to the appropriate array and that array's expected length - you don't need the second parameter because all JavaScript arrays have a .length property.
You don't want to use .slice() to get the individual values out of the array, because that returns a new array copied out of the original - just use arrayVariable[index] to get the individual item at index.
So, putting that together try something like this (with your existing array definitions):
switch(n){
case 1:
changelabels(bodyplan);
break;
case 2:
changelabels(mouthposition);
// etc.
}
function changelabels(data) {
var i,
lbl;
for (i = 0; i < data.length; i++) {
lbl = document.getElementById("rb" + (i+1) + "lbl");
lbl.innerHTML = data[i];
}
}
Notice how much simpler that is than your code? I'm assuming here the elements you are updating have an id in the format "rb1lbl", "rb2lbl", etc, with numbering starting at 1: I'm getting those ids using (i+1) because JavaScript array indexes start at zero. Note also that you don't even need the lbl variable: you could just say document.getElementById("rb" + (i+1) + "lbl").innerHTML = data[i] - however I've left it in so that we have something to expand on below...
Within your function you seem to be changing the labels on a set of elements (radio button labels?), one per value in the array, but you stop when you run out of array items which means any leftover elements will still hold the values from the previous selection (e.g., if the previous selection was "bodyplan" with 8 options and you change to "mouthposition" with only 5 - you probably should hide the 3 leftover elements that would otherwise continue to display the last few "bodyplan" items. One way to do that is instead of setting your loop up based on the array length you could loop over the elements, and if the current element has an index beyond the end of the array hide it, something like this:
function changelabels(data) {
var i,
lbl,
elementCount = 20; // or whatever your element count is
for (i = 0; i < elementCount; i++) {
lbl = document.getElementById("rb" + (i+1) + "lbl");
if (i < data.length) {
lbl.innerHTML = data[i];
lbl.style.display = "";
} else {
lbl.innerHTML = "";
lbl.style.display = "none";
}
}
}
If these elements are labels for radio buttons (just a guess based on the ids) then you'd also want to hide or show the corresponding radio buttons, but I hope you can figure out how to add a couple of lines to the above to do that.
(As mentioned above, be careful about having element ids count up from 1 when the array indexes start at 0.)
If the above doesn't work please post (at least some of) the relevant HTML - obviously I've just had to guess at what it might be like.
SOLUTION: Changed the scope of the array variables to local by moving them into the function where they are used, instead of having them as global variables at the top of the page. I don't understand as I was following every rule of variable declaration. But for some unknown reason, global variables in javascript are abhorrent.
Solution Edit: Found an error in declaring my global variables. This may have been the source of my problem of why I could not access them. But it is a non-issue at this point since I corrected my code.
I don't understand what your trying to achieve exactly with your code. But to pass a variable (in this case an array) by reference you just have to add "&" before the variable.
function the_name(&$var_by_ref, $var_by_value) {
// Here if you modify $var_by_ref this will change the variable passed to the function.
}
More: http://php.net/manual/en/language.references.pass.php
Hope that helps.
I am setting up some basic pagination of a table, and I have the following JS function:
function AddPagination() {
var paginationDiv = document.getElementById("pagination");
for (i = 0; i < 3; ++i) {
var page = document.createElement("a");
page.innerHTML = i + 1;
page.setAttribute("title", i + 1);
page.setAttribute("href", "javascript:RenderResultTable(this.innerHTML)");
paginationDiv.appendChild(page);
}
}
What I want to do is pass page number clicked on to the RenderResultTable method. I have this number stored as the innerHTML and title for the link element, how can I get this passed through using the above code?
Thanks.
Personally, I wouldn't use JavaScript for pagination but if that's the way you want to go, you need to use some string concatenation. I'm not sure what RenderResultTable() does but you can set that line up like this:
page.setAttribute("href", "javascript:RenderResultTable('" + page.innerHTML + "')");
I believe that should do the trick.
EDIT: Shouldn't you be using i++ in your loop instead of ++i? I think what you have right now will give 2 as the first page number. Please correct me if I am wrong.
EDIT: page.innerHTML will need to be escaped by this functions and then unescaped the in the RenderResultTable() function. escape() and unescape(). This is to prevent JavaScript injections and/or accidental bugs.
I'm trying to debug some javascript I wrote and can't figure out why it's not working. If I hard code the variables it works fine, but if I use document.getElementById('id').value to get the variable it fails.
The example below works fine but as soon as I un-comment the commented lines it doesn't. Printing the variables before and after the second section they seem to be identical.
Really don't get what's going on. Maybe I just need to sleep on it, but if anyone's got suggestions that would be great!
roof_width = 5;
roof_depth = 3;
panel_width = 2;
panel_depth = 1;
panel_power = 200;
roof_margin = 0.100;
panel_gap = 0.05;
roof_width = document.getElementById('roof_width').value;
roof_depth = document.getElementById('roof_depth').value;
// panel_width = document.getElementById('panel_width').value;
// panel_depth = document.getElementById('panel_depth').value;
panel_power = document.getElementById('panel_power').value;
// roof_margin = document.getElementById('roof_margin').value;
panel_gap = document.getElementById('panel_gap').value;
Are you trying to add numbers that are in text boxes? Because of the way JavaScript's variable typing system works (combined with the overloading of the + operator), 2 + 2 === 4 (adding numbers) but '2' + '2' === '22' (string concatenation). Try changing the lines to, for example:
panel_width = parseFloat(document.getElementById('panel_width').value);
or alternatively:
panel_width = Number(document.getElementById('panel_width').value);
This will ensure that JavaScript treats the numbers as numbers rather than as strings.
JavaScript parameters can't be called in the same way that you're calling HTML elements. In order to call
document.getElementById('roof_margin').value;
you need to assign 'roof_margin' to an HTML form element.
Pherhaps you have multiple dom elements with the same id? Remember the dom element ID must be unique. I suggest you to use jquery for interacting javascript with html.
Make sure your code is in an onload function. Otherwise the elements may not have been loaded into the DOM yet.
window.onload = funciton(){/* code here */};