Confirm before exiting edited edit form

CHANGELOG.md

@@ -1,4 +1,5 @@
 ## Adminer dev
+- Confirm before exiting edited edit form
 - Display collation at table structure if different from table
 - PostgreSQL: Display auto_increment of inserted rows
 - PostgreSQL: Display description of system variables

adminer/call.inc.php

@@ -81,6 +81,7 @@ if ($in) {
 		echo "\n";
 	}
 	echo "</table>\n";
+	echo script("setupEditChange(qsl('form'));");
 }
 ?>
 <p>

adminer/include/html.inc.php

@@ -337,7 +337,7 @@ function input($field, $value, $function, $autofocus = false) {
 			$first++;
 		}
 		if ($first) {
-			echo script("mixin(qsl('td'), {onchange: partial(skipOriginal, $first), oninput: function () { this.onchange(); }});");
+			echo script("mixin(qsl('td'), {oninput: partial(skipOriginal, $first)});");
 		}
 	}
 }
@@ -513,6 +513,7 @@ function edit_form($table, $fields, $row, $update) {
 			;
 		}
 		echo "</table>\n";
+		echo script("setupEditChange(qsl('form'));");
 	}
 	echo "<p>\n";
 	if ($fields) {

adminer/static/functions.js

@@ -575,6 +575,29 @@ function fieldChange() {
 
 
 
+let editChanged;
+
+/** Setup saving editChanged on form fields
+* @this HTMLFormElement
+*/
+function setupEditChange(form) {
+	for (const el of qsa('input, select, textarea', form)) {
+		el.addEventListener('change', () => {
+			editChanged = true;
+		});
+	}
+	form.onsubmit = () => {
+		editChanged = null; // false doesn't work in Chrome
+	}
+}
+
+onbeforeunload = () => {
+	// all modern browsers ignore string returned from here
+	return editChanged;
+};
+
+
+
 /** Create AJAX request
 * @param string
 * @param function (XMLHttpRequest)