RTCSctpTransport: maxMessageSize property
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since May 2023.
The maxMessageSize read-only property of the RTCSctpTransport interface indicates the maximum size of a message that can be sent using the RTCDataChannel.send() method.
Value
An integer value giving the maximum size, in bytes, of a message which can be sent using the RTCDataChannel.send() method.
Examples
This example shows how you might split up a string into small enough parts to send based on maximum message size.
js
// Function splits strings to a specified size and returns array.
function splitStringToMax(str, maxLength) {
const result = [];
let i = 0;
while (i < str.length) {
result.push(str.substring(i, i + maxLength));
i += maxLength;
}
return result;
}
const peerConnection = new RTCPeerConnection(options);
const channel = peerConnection.createDataChannel("chat");
channel.onopen = (event) => {
const maximumMessageSize = peerConnection.sctp.maxMessageSize;
const textToSend = "This is my possibly overly long string!";
splitStringToMax(textToSend, maximumMessageSize).forEach((elem) => {
channel.send(elem);
});
};
Specifications
| Specification |
|---|
| WebRTC: Real-Time Communication in Browsers # dom-rtcsctptransport-maxmessagesize |
Browser compatibility
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maxMessageSize
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Legend
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- Full support
- Full support