Fgets php
Try…catch statementThe try…catch statement marks a block of expressions to try and specifies one or more responses in case an exception is thrown. If an exception is thrown, the try…catch statement catches it.
The try…catch statement consists of a try block, which contains one or more statements, and a catch block, which contains statements that specify what to do if an exception is thrown in the try block.
In other words, you want the try block to succeed, but if it doesn’t, you want control to pass to the catch block. If any statement within the try block (or in a function called from within the try block) throws an exception, control immediately switches to the catch block. If no exception is thrown in the try block, the catch block is skipped. The block finally executes after the try and catch blocks are executed, but before the statements following the try…catch statement.
The catch block specifies an identifier (catchID in the above syntax) that contains the value specified by the throw statement. You can use this identifier to get information about the exception that was thrown.
Fopen()
CORS is an acronym that refers to the security rules that guarantee the communication between two points with a different precedence to the domain from which it is called (i.e.: different domains).
In the image shown, these rules are activated when trying to deliver/get the information from the server corresponding to “other-domain.mx”, if an exchange is not made according to the server, the web client will cancel the request even before anything else.
Access-Control-Allow-Origin: is a header that is returned to indicate if the response can be shared with the requesting domain. You can indicate the domains you want to share the information with (separated by commas) or an asterisk (*) if you don’t know the origin of your requester.
I would verify that the way I am using to control the access is not among the known cases that present vulnerabilities (the ones presented here are surely not a complete list, but enough to give an idea of where to start).
Php file_get_contents
Si el archivo que está leyendo está en formato CSV no use file(), use fgetcsv(). file() dividirá el archivo por cada nueva línea que encuentre, incluso las nuevas líneas que aparezcan dentro de un campo (es decir, dentro de las citas).
Tenga en cuenta que el uso de file() para contar las líneas puede causar OOM en el servidor ya que asignará todas las líneas en un array.Si está tratando con archivos que pueden tener miles de líneas, SplFileObject podría ser una mejor idea y con pequeños cambios puede obtener el mismo resultado.
Si recibes el mensaje “failed to open stream: Permiso denegado” cuando intentas usar file() o fopen() para acceder a archivos en otro servidor. Comprueba que tu host no tiene ninguna restricción de firewall que impida las conexiones salientes. Este es el caso de mi host Aplus.net
El uso de if ( file(nombre.txt) ) podría no ser suficiente para comprobar si el archivo se abrió con éxito para su lectura, ya que el archivo podría estar vacío, en cuyo caso la matriz devuelta estaría vacía, así que pruebe en su lugar con !==. p. ej.:$matriz_archivo = file(‘prueba. txt’); // un archivo vacíoecho ‘<pre>’;if ( $matriz_de_archivo ) { # código… echo “éxito\n”;} else { # código… echo “fracaso\n”; // ejecutado}if ( $matriz_de_archivo !== false ) { # código… echo “éxito\n”; // ejecutado} else { # código… echo “fracaso\n”;}echo ‘</pre>’;result:fracasoéxito
Open php file
In the permissions dialog that the system displays when you call requestPermissions(), it tells you what permissions your app needs, but not why. This can sometimes confuse the user. It is recommended that you explain why your app needs those permissions before you call requestPermissions().
Some research shows that users are more comfortable with permission requests if they know what the app needs them for, for example, if the permission is needed in order to support a core function of the app or for advertising purposes. Consequently, if you only use a fraction of the API calls that belong to a permission group, it will be easier for you to explicitly state which permissions you use and why. For example, if you only use the approximate location, inform the user in your app description or help articles.
After the user sees an educational UI, or the value displayed by shouldShowRequestPermissionRationale() indicates that you do not need to display an educational UI, request permission. Users see a system permissions dialog where they can choose whether they want to grant a particular permission to your app.
