feat: add new js script Expandable.js

src/Templates/Scripts/Expandable.js

@@ -0,0 +1,34 @@
+const expandables = document.querySelectorAll('.expandable');
+
+expandables.forEach(function(expandable) {
+    const lines = 5;
+    expandable.style.maxHeight = "calc(1.5em * " + lines + ")";
+    expandable.style.overflow = "hidden";
+    if (hasOverflow(expandable, lines)) {
+        addExpandButton(expandable);
+    }
+});
+
+function hasOverflow(element, lines) {
+    if (countBRTags(element) > lines) {
+        return true;
+    }
+    return false;
+}
+
+function addExpandButton(expandable) {
+    var aTag = document.createElement('a');
+    aTag.href = "#"
+    aTag.addEventListener('click', function(event) {
+        event.preventDefault();
+        aTag.style.display = "none";
+        expandable.style.maxHeight = "inherit";
+    });
+    aTag.innerHTML = 'Alle Versionen anzeigen';
+    expandable.insertAdjacentElement('afterend', aTag);
+}
+
+function countBRTags(element) {
+    var brTags = element.innerHTML.match(/<br>/g);
+    return brTags ? brTags.length : 0;
+}