A global merge field type to provide access to a message channel defined in your organization.
Use this expression in your Visualforce page to access a message channel and use the Lightning Message Service APIs.
1<apex:page>
2 <script>
3 // Load the MessageChannel token in a variable
4 var SAMPLEMC = "{!$MessageChannel.SampleMessageChannel__c}";
5 function handleClick() {
6 const payload = {
7 recordId: "some string",
8 recordData: {value: "some value"}
9 }
10 sforce.one.publish(SAMPLEMC, payload);
11 }
12 </script>
13 <div>
14 <p>Publish SampleMessageChannel</p>
15 <button onclick="handleClick()">Publish</button>
16 </div>
17</apex:page>
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