javascript - check if string is in a array without case sensitive [duplicate]

Question

I want to make a filter. Where if you input a word that is in the 'blacklist' it will tell something. I've got all the code but have a problem.

JS:

input = document.getElementById("input").value;
array = ["1","2","3"];
function filter() {
  if (input == array)
  // I will do something.
  } else {
  // Something too
  }
}

I want to make it so that if the input is a item in the array. That the statement is true. But what is the correct way to do this? Because what I'm doing here doesn't work! Also I want to get rid of the case sensitive! So that if the array has hello in it both hello and Hello are detected.

Sorry if this question is asked before. I searched for it but didn't know what keywords to use.

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EDIT 1:

I am changing my question a little bit: I want to check what is in my original question but with some other features.

I also want to check if input has a part of an item in array. So that if the input is hello that helloworld is being detected because is has hello in it. As well as hello or Hello.

Answer 1

Use indexOf:

if (array.indexOf(input) > -1)

It will be -1 if the element is not contained within the array.

Answer 2

This code should work:

input = document.getElementById("input").value;
array = ["1","2","3"];
function filter() {
   if (array.indexOf(input) >= 0)
      // I will do something.
    } else {
      // Something too
    }
}

The indexOf Method is member of the array type and returns the index (beginning at 0) of the searched element or -1 if the element was not found.