diff --git a/client/src/common/cdlEventHandler.ts b/client/src/common/cdlEventHandler.ts
index b6282c9..7b750ed 100644
--- a/client/src/common/cdlEventHandler.ts
+++ b/client/src/common/cdlEventHandler.ts
@@ -1,6 +1,7 @@
 export interface CdlEventHandler {
     eventName: string
     parameterNames: string[]
+    toggleOffParameterNames?: string[]
 }
 
 function structuralCode(line: string): string {
@@ -33,18 +34,6 @@ function structuralCode(line: string): string {
     return result
 }
 
-function braceDelta(line: string): number {
-    let delta = 0
-    for (const character of structuralCode(line)) {
-        if (character === "{") {
-            delta += 1
-        } else if (character === "}") {
-            delta -= 1
-        }
-    }
-    return delta
-}
-
 export function cdlEventHandlerAtLine(
     source: string,
     declarationLine: number
@@ -61,35 +50,44 @@ export function cdlEventHandlerAtLine(
     }
 
     const parameterNames: string[] = []
+    const toggleOffParameterNames: string[] = []
+    let currentParameter: string | undefined
     let eventOpened = false
     let depth = 0
 
-    for (let lineNumber = declarationLine; lineNumber < lines.length; lineNumber++) {
+    eventLines: for (let lineNumber = declarationLine; lineNumber < lines.length; lineNumber++) {
         const line = lines[lineNumber]
         const code = structuralCode(line)
 
-        if (eventOpened && depth === 1) {
-            const parameterMatch = /^\s*PARAM\s+([^\s{]+)/.exec(code)
-            if (parameterMatch) {
-                parameterNames.push(parameterMatch[1])
-            }
-        }
-
-        const delta = braceDelta(line)
-        if (!eventOpened && delta > 0) {
-            eventOpened = true
-        }
-        if (eventOpened) {
-            depth += delta
-            if (depth <= 0) {
-                break
+        const tokens = code.match(/[{}]|[^\s{}]+/g) ?? []
+        for (let index = 0; index < tokens.length; index++) {
+            const token = tokens[index]
+            if (token === "{") {
+                eventOpened = true
+                depth++
+            } else if (token === "}" && eventOpened) {
+                depth--
+                if (depth === 1) currentParameter = undefined
+                if (depth <= 0) break eventLines
+            } else if (depth === 1 && token === "PARAM") {
+                const name = tokens[index + 1]
+                if (name && name !== "{" && name !== "}") {
+                    currentParameter = name
+                    parameterNames.push(name)
+                    index++
+                }
+            } else if (depth === 2 && currentParameter && token === "TOGGLE") {
+                if (tokens[index + 1]?.toLowerCase() === "off") {
+                    toggleOffParameterNames.push(currentParameter)
+                }
             }
         }
     }
 
     return {
         eventName: eventMatch[1],
-        parameterNames
+        parameterNames,
+        toggleOffParameterNames
     }
 }
 
@@ -102,8 +100,12 @@ function momVariableName(parameterName: string): string {
 }
 
 export function createCdlEventHandlerSnippet(handler: CdlEventHandler): string {
+    const toggleOffParameters = new Set(handler.toggleOffParameterNames ?? [])
     const globals = [
-        ...new Set(handler.parameterNames.map((parameter) => momVariableName(parameter)))
+        ...new Set(handler.parameterNames.flatMap((parameter) => {
+            const variable = momVariableName(parameter)
+            return toggleOffParameters.has(parameter) ? [variable, `${variable}_defined`] : [variable]
+        }))
     ]
     const lines = [`proc ${momEventName(handler.eventName)} {args} {`]
 
diff --git a/test/cdlEventHandler.test.js b/test/cdlEventHandler.test.js
new file mode 100644
index 0000000..6276870
--- /dev/null
+++ b/test/cdlEventHandler.test.js
@@ -0,0 +1,51 @@
+const assert = require("node:assert/strict")
+const fs = require("node:fs")
+const path = require("node:path")
+const vm = require("node:vm")
+const { test } = require("node:test")
+const { transformSync } = require("esbuild")
+
+const source = fs.readFileSync(path.join(__dirname, "../client/src/common/cdlEventHandler.ts"), "utf8")
+const compiled = transformSync(source, { loader: "ts", format: "cjs" }).code
+const context = { module: { exports: {} } }
+vm.runInNewContext(compiled, context)
+const { cdlEventHandlerAtLine, createCdlEventHandlerSnippet } = context.module.exports
+
+test("TOGGLE Off adds the defined globals to the event handler", () => {
+    const cdl = `EVENT GDM_header
+{
+    PARAM product_status {
+        TYPE o
+        OPTIONS "Serie", "Prototyp"
+    }
+    PARAM stm_param_mpf_name
+    {
+        TYPE s
+        TOGGLE Off
+    }
+    PARAM stm_param_wks_path {
+        TYPE s
+        TOGGLE Off
+    }
+}`
+    const snippet = createCdlEventHandlerSnippet(cdlEventHandlerAtLine(cdl, 0))
+    assert.match(snippet, /global mom_stm_param_mpf_name_defined/)
+    assert.match(snippet, /global mom_stm_param_wks_path_defined/)
+    assert.match(snippet, /global mom_product_status\n/)
+    assert.doesNotMatch(snippet, /mom_product_status_defined/)
+})
+
+test("toggle detection ignores comments, strings, other events, and TOGGLE On", () => {
+    const cdl = `EVENT first {
+        PARAM plain { TYPE s UI_LABEL "TOGGLE Off { ignored }" }
+        PARAM enabled { TOGGLE On }
+        PARAM commented { TYPE s # TOGGLE Off
+        }
+        PARAM mom_disabled { TOGGLE off }
+    }
+    EVENT second { PARAM other { TOGGLE Off } }`
+    const snippet = createCdlEventHandlerSnippet(cdlEventHandlerAtLine(cdl, 0))
+    assert.match(snippet, /global mom_disabled_defined/)
+    assert.equal((snippet.match(/_defined/g) ?? []).length, 1)
+    assert.doesNotMatch(snippet, /mom_mom_|mom_other/)
+})