TransformStream: readable property
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since June 2022.
Note: This feature is available in Web Workers.
The readable read-only property of the TransformStream interface returns the ReadableStream instance controlled by this TransformStream. This stream emits the transformed output data.
Value
Examples
This example creates a TransformStream that converts all input text to uppercase letters. It writes some text to the writable stream, then reads the transformed text from the readable stream.
js
const stream = new TransformStream({
transform(chunk, controller) {
controller.enqueue(chunk.toUpperCase());
},
});
// Write data to be transformed
const writer = stream.writable.getWriter();
writer.write("hello ");
writer.write("world");
writer.close();
// Read transformed data
const reader = stream.readable.getReader();
let done = false;
let output = "";
while (!done) {
const result = await reader.read();
if (result.value) {
output += result.value;
}
done = result.done;
}
console.log(output); // HELLO WORLD
Specifications
| Specification |
|---|
| Streams # ref-for-ts-readable② |