package org.springblade.common.utils;

import org.springframework.web.multipart.MultipartFile;

import java.io.File;
import java.io.IOException;

public class FileUtil {

	/**
	 * MultipartFile 转 file
	 * @param multipartFile
	 * @return
	 */
	public static File toFile(MultipartFile multipartFile) {
		// 如果multipartFile为空，则直接返回null
		if (multipartFile == null) {
			return null;
		}
		// 创建一个临时的文件
		File file = null;
		try {
			file = File.createTempFile("temp", multipartFile.getOriginalFilename());
			multipartFile.transferTo(file);
		} catch (IOException e) {
			e.printStackTrace();
		}
		return file;
	}

	/**
	 * 获取文件后缀
	 * @param file
	 * @return
	 */
	public static String getFileExtension(MultipartFile file) {
		String originalFilename = file.getOriginalFilename();
		String extension = "";
		if (originalFilename != null) {
			int dotIndex = originalFilename.lastIndexOf(".");
			if (dotIndex >= 0) {
				extension = originalFilename.substring(dotIndex + 1);
			}
		}
		return extension;
	}
}