I tried using the join() function in my array and tried to document.write it but the console says"birth.join() is not a function "
birthyear=[];
for(i=1800;i<2018;i++){
birthyear+=i
}
birth=birthyear.join();
document.write(birth);
3 Answers
Array.prototype.join() works on array and to insert an element to array you should call .push() instead of +=, read more about += here.
Always use var before declaring variables, or you end up declaring global variables.
var birthyear = [];
for (i = 1800; i < 2018; i++) {
birthyear.push(i);
}
var birth = birthyear.join(", ");
document.write(birth);
Comments
I your code your not appending data to array you are adding data to array variable which is wrong
1st Way
birthyear=[]; for(i=1800;i<2018;i++) { birthyear.push(i); } birth=birthyear.join(); document.write(birth);2nd Way
birthyear=[]; k=0; for(i=1800;i<2018;i++){ birthyear[k++]=i; } birth=birthyear.join(); document.write(birth);
1 Comment
Jay Shankar Gupta
or you can use birthyear=[]; for(i=1800;i<2018;i++){ birthyear.push(i); } birth=birthyear.join(); document.write(birth);
You can't apply .push() to a primitive type but to an array type (Object type).
You declared var birthyear = []; as an array but in the body of your loop you used it as a primitive: birthyear+=i;.
Here's a revision:
var birthyear=[];
for(let i=1800;i<2018;i++){
birthyear[i]=i;
// careful here: birthyear[i] += i; won't work
// since birthyear[i] is NaN
}
var birth = birthyear.join("\n");
document.write(birth);Happy coding! ^_^
console.log(birthyear);would’ve revealed the reason for the error.