matlab：检查xls文件是否打开

Question

我试图编写一个代码来检查文件是否打开。如果是这样，当文件未关闭时，将在屏幕上显示警告消息。

我想我并没有因为这样正确地使用“FCLOSE”，我得到了错误：

??? Error using ==> fclose 
Invalid file identifier. Use fopen to generate a valid file identifier. 

Error in ==> fileisopen at 4 
fclose(fid); 

我想没有FCLOSE功能，它的工作原理，但是当我打开文件我有一个消息，该文件只用于阅读。

这是我的代码：

path_of_file = 'C:\Documents and Settings\erezalon\Desktop\data.xls'; 

[fid msg_file] = fopen(path_of_file, 'a'); 
fclose(fid); 
while (fid == -1) 
    errormsg = strcat('the file: ', path_of_file, ' is open. please close it!'); 
    waitfor(msgbox(errormsg,'Error')); 
    [fid msg_file] = fopen(path_of_file, 'a'); 
    fclose(fid); 
end 

Answer 1

我succeded！这是解决方案：

path_of_file = 'C:\Documents and Settings\erezalon\Desktop\data2.xls'; 

fid = fopen(path_of_file, 'a'); 
if fid ~= -1 
    fclose(fid); 
else 
    while (fid == -1) 
     errormsg = strcat('the file: ', path_of_file, ' is open. please close it!'); 
     waitfor(msgbox(errormsg,'Error')); 
     fid = fopen(path_of_file, 'a'); 
    end 
    fclose(fid); 
end