PHP fopen function read and write txt file implementation program

Simple reference to fopen functions

The fopen () function opens a file or URL.

If opening fails, this function returns FALSE.

Syntax
Fopen (filename, mode, include_path, context)

Instance 1

Example of creating a file:

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<? Php If (! File_exists ("test.txt") {// if the file does not exist (the default value is in the current directory) $ Fh = fopen ("test.txt", "w "); Fclose ($ fh); // close the file } ?>

Instance 2

Modify and edit a robots file using php's ability to read and write text documents

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<? Php Function get_txt ($ robots_file) // Define the function. The content is included in {}. { If (file_exists ($ robots_file )) // If the object exists, read the content. { $ Fp = @ fopen ($ robots_file, "r "); // R is the abbreviation of read, which indicates reading. Open a file in read-only mode. If ($ fp ){ While (! Feof ($ fp) {// if it is not at the end of the file $ Robots_txt = fgets ($ fp, 4096); // read data row by row $ Robots_all = $ robots_all. $ robots_txt; // save the data to $ robots_all. } Return ($ robots_all); // return all content Fclose ($ fp); // close the file } } }    Function put_txt ($ robots_txt) { $ Fp = fopen ("robots.txt", "w "); // W is the abbreviation of write, which indicates the meaning of writing. Open the file as a write. Fputs ($ fp, $ robots_txt ); // Output text to a file Fclose ($ fp ); } ?>    <? Php $ Edit = $ _ GET ["edit"]; $ Txt = $ _ POST ["txt"]; $ Get_txt = get_txt ("robots.txt "); // Call the defined function to open the robots file.    If ($ edit = "write ") { Put_txt ($ txt ); Echo "successfully saved <a href = robots-editer.php> back </a> "; } Else { Echo "<a hrefw.robots.txt target = _ blank> robots.txt </a> <a href = writer. php> returned </a> "; } ?>    <? Php If ($ edit = "") { ?> <Form name = "form1" action = "? Edit = write "method =" post "> <Textarea name = "txt" cols = "160" rows = "30"> <? Php echo $ get_txt;?> </Textarea> <Br/> <Input name = "submit" value = "save" type = "submit"/> </Form> <? Php } ?>

Read the data in the counter.txt file through php and save it to the text document with + 1.

Create a counter. php document and enter the following code. Unlike ASP, single-line comments in PHP are implemented with // or #, and multi-line comments are implemented:

 

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<? Php Function get_hit ($ counter_file) // Define the function. The content is included in {}. It should be similar to the C language. { $ Count = 0; // Returns the counter to zero. Add the $ sign before the variable in Php.    If (file_exists ($ counter_file )) // If the counter file exists, read the content { $ Fp = fopen ($ counter_file, "r "); // R is the abbreviation of read, which indicates reading. Open a file in read-only mode. $ Count = 0 + fgets ($ fp, 20 ); /* Assign the value of the first 20 digits to the count variable. Because the fgets () function reads strings, you must convert them to integers by adding + 0, This is different from ASP. Strings in ASP can be directly computed with integers without conversion. */ Fclose ($ fp ); // Close the file } $ Count ++; // Increase the count, which is very similar to C. $ Fp = fopen ($ counter_file, "w "); // W is the abbreviation of write, which indicates the meaning of writing. Open the file as a write. Fputs ($ fp, $ count ); // Output the count value to the file Fclose ($ fp ); Return ($ count ); // Return the count value } ?>    <? Php $ Hit = get_hit ("counter.txt "); // Call the just-defined counter to process the counter.txt document and assign the result to the hit variable. Echo "you are the <B>". "$ hit". "</B> guest! "; // Output the result. The difference between PHP and ASP is that the connection character of ASP is "&", while that of Php is ".". ?>

Also insert this file in the PHP document to be called:

<? Php include ("counter. php");?>