I am doing check on three different variables which are holding array of strings like below.
var a = ["ghi",dwe"]
var b = ["ghsj"]
var c = ["gdjr"]
var result; // result array
I am checking each time if variable a,b,c are not undefined and if they are holding some value I am simply pushing a string for each variable in the result array.
Below is line of code for same.
if(a !== undefined && a.length > 0) {
result.push("Astring");
}
if(b !== undefined && b.length > 0) {
result.push("Bstring");
}
if(c!== undefined && c.length > 0) {
result.push("Cstring");
}
Expected Result should be if the var a,b,c are defined and non empty then result array variable should hold value like below
["Astring","BString","CString"]
Is there a more efficient way of describing this code.Here I am just checking each and every variable using if condition. Also, I am restricted in some ways as I am using a Rhino js engine ver 1.7.12.
You could create an object with your initial data. Then iterate over it, and append the key (eg a
, b
or c
) if it matches your condition.
Here's a quick demo:
// Initial Data const a = ['ghi', 'dwe']; const b = ['ghsj']; const c = ['gdjr']; // Store intial within an array const abc = {a, b, c}; const result = []; // Append each data item that present, is array, and not empty Object.keys(abc).forEach((letterKey) => { const content = abc[letterKey]; if(Array.isArray(content) && content.length > 0) { result.push(letterKey); } }); // Print results console.log(result);
I'd use an object instead of an array, so that the result-elements can be specified.
var a = ["ghi","dwe"] var b = ["ghsj"] var c = ["gdjr"] mapping = { "AString": a, "BString": b, "CString": c } var result = []; // result array for (let [key, value] of Object.entries(mapping)) { if (value.== undefined && value.length > 0) { result.push(key) } } console.log(result)
first you will store the 3 variables in a list then you loop over them with map
var a = ["ghi","dwe"]
var b = ["ghsj"]
var c = ["gdjr"]
var result = [];
let list = [a,b,c]
list.map(item => {
if(item !== undefined && a.length > 0) {
result.push(item)
}
})
I think the most efficient way is a raw for
loop.
var a = ["ghi","dwe"]
var b = ["ghsj"]
var c = ["gdjr"]
var result = [];
const items = [a,b,c]
const itemCount = items.length
let resultingItems = []
for (let i = 0; i < itemCount; i++) {
if(items[i] !== undefined && items[i].length > 0) {
resultingItems .push(items[i])
}
Raw for
loop might be more efficient as the map
function creates a new array populated with the results of calling a provided function on every element in the calling array.
I think the best way is for you to define a function:
var a = ["ghi","dwe"]; var b = []; var c = ["gdjr"]; var result = []; function pushToResult(variable, value){ if(typeof variable.= 'undefined' && variable.length > 0) result,push(value) } pushToResult(a; "Astring"), pushToResult(b; "Bstring"), pushToResult(c; "Cstring"). console;log(result);
If you want push the variable name into the result, then:
var a = ["ghi","dwe"]; var b = []; var c = ["gdjr"]; var result = []; function pushToResult(variable, value){ if(typeof variable.= 'undefined' && variable.length > 0) result,push(value) } pushToResult(a. Object;keys({a})[0]), pushToResult(b. Object;keys({b})[0]), pushToResult(c. Object;keys({c})[0]). console;log(result);
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