diff --git a/src/Fasim/Widget/Form.php b/src/Fasim/Widget/Form.php
index aecdfa1..5be47b0 100644
--- a/src/Fasim/Widget/Form.php
+++ b/src/Fasim/Widget/Form.php
@@ -513,11 +513,16 @@ public function renderInput() {
 
 class FormImages extends FormGroup {
 	public $maxCount = 6;
+	public $allowFiles = 'jpg,jpeg,gif,png';
 
 	public function maxCount($maxCount) {
 		$this->maxCount = $maxCount;
 	}
 
+	public function allowFiles($allowFiles) {
+		$this->allowFiles = $allowFiles;
+	}
+
 
 	public function renderInput() {
 		$fileId = 'i_'.$this->key;
@@ -543,7 +548,7 @@ public function renderInput() {
 		pick: '#{$filePickerId}',
 		accept: {
 			title: '上传文件',
-			extensions: '{$this->allowFiles},
+			extensions: '{$this->allowFiles}',
 			mimeTypes: 'image/*'
 		}
 	});