bufferCount

Accumulates values into a fixed-length array and emits it.

Signature

bufferCount(bufferSize: number, startBufferEvery?: number): OperatorFunction

Marble diagram

in:           --1-2-3-4-5--|
bufferCount(2): ----[1,2]-[3,4]-[5]-|

What it does

Collects next values into an array of length bufferSize and emits the finished buffer. When the stream completes, it emits the remainder (even if smaller than bufferSize). The startBufferEvery parameter controls sliding windows.

When to use

Batching events before sending (logs, analytics), grouping WebSocket messages, chunked loading.

See also

bufferTime, window, pairwise