I'm not sure if this is a stupid question but can I write something that returns a substring without using substrings?
for e.g. usually you'd write something like this:
var str = "Hello world";
var res = str.substring(1, 4);
Can i use a loop instead to do it? Or is that not possible? How would i start to do it? I know it's something to do with arrays.
would it be something like A[i] and adding loops?
You could do something like this if you really want to use an array and indexes:
var str = "Hello world";
var res = "";
var first_char = 1; // inclusive
var last_char = 4; // exclusive
for(var i = first_char; i < last_char; i++) {
res += str[i];
}
alert(res);but can I write something that returns a substring without using substrings?
Not sure why you don't want to use substring, hope there is no issue with slice
str.slice(1,5); //outputs "ello"
or, if you want to make it more complicated then
str.split("").splice(1,4).join(""); //outputs "ello"
this one treats str as array and then filter out the data based on index
str.split("").filter( function(value, index){ if ( index >= 1 && index < 5 ) {return true;} else {return false;} } ).join(""); //outputs "ello"
+=for concatenation...Try this:var str = "Hello world"; var op = ''; for (var i = 1; i < 4; i++) { op += str[i]; } alert(op); var res = str.substring(1, 4); alert(res);var str = "Hello world"can be treated as an array. So, if you runstr[0]you will get"H".