When trying to use window.FormData I get the following error:

The name 'FormData' does not exist in the current scope

The same happens to FileReader

When trying to use window.FormData I get the following error:

The name 'FormData' does not exist in the current scope

The same happens to FileReader

• javascript
• typescript

• It should, as there's an issue about it, fixed already. What version of TypeScript is used? – raina77ow Commented May 31, 2013 at 22:57
• 1 Weird. Ok, what if you use FormData without window prefix? – raina77ow Commented May 31, 2013 at 23:06
• What browser are you using ? – Russ Clarke Commented May 31, 2013 at 23:07
• Ah, so it does recognize FormData, but now how can I check if the browser supports it? Im using code that checks for window.FormData to search for browser support. – localhost Commented May 31, 2013 at 23:10

2 Answers 2

add dom to the lib array in the tsconfig.json of your project.

{
  "compilerOptions": {
    ...
    "lib": ["es2018", "dom"], // add `dom` to the array
    ...
  }
}

You can check a feature exists using:

if (window.FormData) {
    alert('Yes');
}

This relies on falsey checks - if you want to be explicit, use.

if (typeof FormData !== 'undefined') {
    alert('Yes');
}