Looping through json

Question

Hi guys assume you have a json object like this
{
meal:beans,
Image:pexels.com
Health :true
ingredient1:onions,
ingredient2:potatoes,
ingredient3:beans,
}
How do you loop through to console.log all your ingredients, assuming your object has 25 ingredients

Answer 1

for ( var key in myJSON){
if ( key.indexOf("ingredient") == 0){
console.log(myJSON[key]);
}
}

Answer 2

The for...in loop is intended for iterating over the enumerable keys of an object.
https://www.sololearn.com/learn/JavaScript/2970/?ref=app
That's how it moves to the next object key. This iterates over ALL enumerable keys but we only want to log the "ingredients".

indexOf is a string method that returns the index where a given string is located in the string that called the method. -1 is returned when the substring is not found.
E.g:
"abcdef".indexOf ("b") == 1; //true
"abcdef".indexOf ("bcdef") == 1; //true
"abcdef".indexOf ("fgh") == -1; //true

The if statement could be read this way:
if (the key has "ingredient" as a substring [from index 0] )
Then console.log(myJSON [key] ) to get the value.

or

if (the key starts with "ingredient")
Then log the value.

In ES6 and above the if statement is easier to write and read :

if(key.startsWith("ingredient"){
console.log(myJSON [key])
}

John Bryan You are very welcome.

Answer 3

Got it
Thanks Kevin Star

Answer 4

This worked
But could you please explain the if statement

Isn't the 0 supposed to increment(++) or how does it move to the next ingredient