判断标准DICOM文件

 FILE * fp = fopen("C:\Nero.rar","rb");
     if (fp == NULL)
     {
        return;
     }
     if (!fseek(fp,128,SEEK_SET)) //直接跳过文件导言   
     {   
        char  DICOM[5];   
        fread(DICOM,1,4,fp);   
        DICOM[4] = '\0';   
        if (strcmp(DICOM,"DICM")) 
        {
            MessageBox("不是dicom");
        }
        else
        {
            MessageBox("是dicom");
        }
     }