In-depth explanation of how to operate php files

$path1= "F:/www/jbxue.txt";
if(!file_exists($path1)){
 echo "The file does not exist!";
}else{
 $ handle1 = fopen($path1, 'r+') or exit("Unable to open file");
// while (!feof($handle1)){
// echo fgets($handle1)." ";
// }
 while(!feof($handle1)){
 echo fgetc($handle1);
 }
}
?>

The above implements a simple file reading Get the operation.

Instructions: fopen is to open file resources. Instructions: $file=fopen("welcome.txt","r"); Specific meaning: The first parameter is the path of the file. The following parameters are required to use the method to open the file, there are the following types:

r Read only. Start at the beginning of the file. r+ read/write. Start at the beginning of the file. w write only. Opens and clears the contents of the file; if the file does not exist, creates a new file. w+ read/write. Opens and clears the contents of the file; if the file does not exist, creates a new file. a append. Opens and writes to the end of a file, or creates a new file if it does not exist. a+ read/append. Maintain file contents by writing to the end of the file. x Write only. Create new file. Returns FALSE if the file already exists. x+ read/write. Create new file. If the file already exists, returns FALSE and an error.

Note: If fopen() cannot open the specified file, it returns 0 (false). The more commonly used ones are the first 4. fgetc: string fgetc(resource$handle) Returns a string containing one character obtained from the file pointed to by handle. Returns FALSE if EOF is encountered. fgets: string fgets ( int$handle [,int$length ] ) Reads a line from the file pointed to by handle and returns a string of length at most length - 1 bytes. Stops when a newline character (included in the return value), EOF, or length - 1 bytes has been read (whichever occurs first). If length is not specified, it defaults to 1K, or 1024 bytes. Returns FALSE on error. fgetss: string fgetss ( resource$handle [,int$length [,string$allowable_tags ]] ) Same as fgets(), except fgetss attempts to strip any HTML and PHP tags from the text being read. (Same as fgets(), except that it filters html and php tags.) The optional third parameter can be used to specify which tags are not to be removed. The feof() function detects whether the end of file (eof) has been reached.

//Determine whether the file or directory exists bool file_exists(string filename) Determines whether the file or directory exists, returns true if it exists, otherwise returns false Format: if(file_exists(“hello.txt”)) { Echo "File exists"; } //open a file Format: fopen(filename,mode) Description: Open the specified file in the specified format filename: the name of the file to be opened mode : open mode fopen("hello.txt","w"); Indicates opening the hello.txt file in writing mode //write file Format: fwrite(resource,string); Description: Add the specified content to the opened file resource:open file string: the content to be written example: $handle = fopen("hello.txt","w") //If a, data can be appended fwrite($handle,”1rn”) //Close file Format: fclose($handle) Description: Close the open file example: $handle = fopen("hello.txt","w"); fclose($handle); //Read a row of data Format: fgets(int handle[,int length]) Description: Read length-1 characters. If length is not specified, the default byte is 1KB. If a newline, EOF or length-1 characters have been read, the program will terminate and false will be returned in case of error; 1 2 Next page last page