I have this code, repeating 20 times with only change of variables prefix. How can i possibly make a loop and iterate by it to avoid this huge block of code? It is used in my website and I want to make the development process more clear.
var keepElements = document.getElementsByName("keep-type");
for(var i = 0; i < keepElements.length; i++){
keep = document.getElementById(keepElements[i].value);
if(keepElements[i].checked == true){
keep.style.display = "block";
}
else{keep.style.display = "none";}
}
var offworkshopElements = document.getElementsByName("offworkshop-type");
for(var i = 0; i < offworkshopElements.length; i++){
offworkshop = document.getElementById(offworkshopElements[i].value);
if(offworkshopElements[i].checked == true){
offworkshop.style.display = "block";
}
else{offworkshop.style.display = "none";}
}
var defworkshopElements = document.getElementsByName("defworkshop-type");
for(var i = 0; i < defworkshopElements.length; i++){
defworkshop = document.getElementById(defworkshopElements[i].value);
if(defworkshopElements[i].checked == true){
defworkshop.style.display = "block";
}
else{defworkshop.style.display = "none";}
}
Move the logic to a function:
function keepElements(name) {
var keepElements = document.getElementsByName(name);
for (var i = 0; i < keepElements.length; i++) {
keep = document.getElementById(keepElements[i].value);
if (keepElements[i].checked == true) {
keep.style.display = "block";
}
else { keep.style.display = "none"; }
}
}
keepElements("keep-type");
keepElements("offworkshop-type");
keepElements("defworkshop-type");
The answers saying you should put the common functionality into a single function are absolutely right.
I just wanted to add that there are also solutions on the query side of things:
you could have all the elements be collected in one javascript function, querySelectorAll()
const elements = document.querySelectorAll('[name="keep-type"], [name="offworkshop-type"], [name="defworkshop-type"]')
Alternatively you could give them all the same class and select by that class.
const elements = document.getElementsByClassName("requiredElements");
And this way you have all your elements in one array.
If I didn't miss any details, you're repeating the same block 3 times:
["keep-type", "offworkshop-type", "defworkshop-type"].forEach(name => {
var elements = document.getElementsByName(name);
for(var i = 0; i < elements.length; i++){
element = document.getElementById(elements[i].value);
if(elements[i].checked == true){
element.style.display = "block";
}
else{element.style.display = "none";}
}
});
I prefer the array / forEach syntax, because the block starts with the list of name. But you could use a for...of loop instead.
for (const name of ["keep-type", "offworkshop-type", "defworkshop-type"]) {
var elements = document.getElementsByName(name);
for(var i = 0; i < elements.length; i++){
element = document.getElementById(elements[i].value);
if(elements[i].checked == true){
element.style.display = "block";
}
else{element.style.display = "none";}
}
}