Xrm.WebApi form script basics

Form scripts are still the quickest way to add smart behaviour to a model-driven app. Xrm.WebApi gives you promise-based access to Dataverse without building URLs by hand.

Register the handler

Add your web resource to the form, then register Unplugged.Account.onLoad on the OnLoad event and tick Pass execution context.

JavaScript

var Unplugged = Unplugged || {};
Unplugged.Account = {
  onLoad: async function (executionContext) {
    const formContext = executionContext.getFormContext();
    const contact = formContext.getAttribute("primarycontactid").getValue();
    if (!contact) return;

    try {
      const id = contact[0].id.replace(/[{}]/g, "");
      const result = await Xrm.WebApi.retrieveRecord("contact", id, "?$select=emailaddress1,jobtitle");
      formContext.ui.setFormNotification(
        `Primary contact: ${result.jobtitle ?? "No job title"} · ${result.emailaddress1 ?? "no email"}`,
        "INFO",
        "primary-contact"
      );
    } catch (e) {
      console.error(e);
    }
  },
};

Keep it maintainable

Use a namespace object so functions don't clash with other scripts.
Use $select to fetch only the columns you need.
Prefer business rules for simple show/hide logic, and save JavaScript for what they can't do.

Register the handler

Read a related record

Keep it maintainable

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