完成上传组件的开发

app/common.php

@@ -176,6 +176,28 @@ function format_bytes($size, $delimiter = '') {
 }
 
 
+/**
+ * 获取附件信息
+ * @param int $cover_id
+ * @param string $field
+ * @return 完整的数据  或者  指定的$field字段值
+ */
+function get_attach($id, $field = null) {
+	$basePath = request()->domain();
+	if (empty($id)) {
+		return $basePath . '/static/images/default.png';
+	}
+	$picture = \think\facade\Db::name('Attach')->where(array('id' => $id))->find();
+	if ($field == 'path') {
+		if (!empty($picture['url'])) {
+			$picture['path'] = $picture['url'] ? $$basePath . $picture['url'] : $$basePath . '/static/images/default.png';
+		} else {
+			$picture['path'] = $picture['path'] ? $$basePath . $picture['path'] : $$basePath . '/static/images/default.png';
+		}
+	}
+	return empty($field) ? $picture : $picture[$field];
+}
+
 /**
  * 获取文档封面图片
  * @param int $cover_id