Home Backend Development PHP Tutorial Basic operations on PHP files

Basic operations on PHP files

Jul 25, 2016 am 08:42 AM

  1. //Basic file operations
  2. //fopen()
  3. Open a file
  4. //Open a file using an absolute path, select read-only mode, and return the resource $handle
  5. $handle= fopen("D:/lamp/apache2/htdocs/test/file.txt","r");
  6. //Access files in the document root directory and also select read-only mode
  7. $handle=fopen($_SERVER[' DOCUMENT_ROOT']."/test/file.txt","r");
  8. //Open remote files, which can only be opened in read mode using the http protocol
  9. $handle=fopen("http://www.wowsai. com","r");
  10. //Use FTP protocol to open remote files. If the FTP server is writable, it can be opened in write mode
  11. //$handle=fopen("ftp://user:password@example. com/file.txt",'w');
  12. //fclose()
  13. Close the open resource type
  14. //fwrite()
  15. Write content to the file
  16. $fileName="data.txt";
  17. // Declare a file variable
  18. //Open the file in write-only mode, create it if it does not exist, and pass the program when the opening fails
  19. $f_handle=fopen("data.txt","w")or die("Open< b>".$fileName."File failed");
  20. for($i=0;$i<10;$i++){
  21. //Add content to the file through a loop
  22. fwrite ($f_handle,"againn");
  23. }
  24. fclose($f_handle);
  25. //Close the open file
  26. //file_put_contents()
  27. Write all data to the specified file at once
  28. //Read the file content
  29. //fread()
  30. Read an open file
  31. //file_get_contents()
  32. Read a file into a string
  33. //fgets()
  34. Return a line from an open file
  35. //fgetc()
  36. From an open file Return characters in
  37. //file()
  38. Read the file into an array
  39. //readfile()
  40. Read a file and output it to the output buffer
  41. //feof()
  42. Judge whether a file pointer is at the end of the file At
  43. //Read the specified number of bytes from the file and store it in a variable
  44. $fileName2="data.txt";
  45. $f_hand=fopen($fileName2,"r")or die("Open the file Failed");
  46. $contents=fread($f_hand,50);
  47. fclose($f_hand);
  48. echo $contents."
    ";
  49. //Read all the contents from the file and store them in a variable , read part of it each time, read in a loop
  50. /* $fileName3="D:/lamp/apache2/icons/link.gif";
  51. //Save the file name of the binary file into a variable
  52. $f3_handle= fopen($fileName3,"rb")or die("File opening failed"); //Open the file in read-only mode, the mode is added with "b"
  53. $f3_contents="";
  54. //Declare one for saving String of file content
  55. while(!feof($f3_handle)){
  56. //Loop to read the contents of the file until the end of the file
  57. $f3_contents.=fread($f3_handle,1024);
  58. //Read each time 1024 characters
  59. }
  60. fclose($f3_handle);
  61. echo $f3_contents; */
  62. //Another way to read the entire contents of the file
  63. $fileName4="data.txt";
  64. $f4_handle=fopen($fileName4 ,"r")or die("File opening failed");
  65. $f4_con=fread($f4_handle,filesize($fileName4));
  66. //Use filesize to get the length of the file, so as to read the entire content of the file
  67. fclose($f4_handle);
  68. echo $f4_con."
    ";
  69. //Another method to read the entire contents of the file, which has much better performance than the above
  70. echo file_get_contents("data.txt");
  71. $f5_handle=fopen("data.txt","r") or die("File opening failed");
  72. while(!feof($f5_handle)){
  73. //Determine whether the pointer reaches the end of the file
  74. $buffer= fgets($f5_handle);
  75. //Read one line from the file at a time
  76. echo $buffer."
    ";
  77. }
  78. fclose($f5_handle);
  79. $f6_handle=fopen("data.txt", "r") or die("File opening failed");
  80. while(!feof($f6_handle)){
  81. //Judge whether the pointer reaches the end of the file
  82. $buffer=fgetc($f6_handle);
  83. //Every time from Read a character from the file
  84. echo $buffer."
    ";
  85. }
  86. fclose($f6_handle);
  87. print_r(file("data.txt"));
  88. //Read the file into an array
  89. readfile("data.txt");
  90. //Read the contents of the file directly and output it to the browser
  91. //Access remote files
  92. Make sure "allow_url_fopen" in php.ini is turned on, and make sure The remote file has access permission
  93. $ws_file=fopen("http://www.wowsai.com","r")or die("Remote file opening failed");
  94. //Open the remote file
  95. while(!feof( $ws_file)){
  96. $ws_line=fgets($ws_file);
  97. if(preg_match("/(.*)/",$ws_line,$res)){
  98. //Use Regularly matches the title of the website
  99. $title=$res[1];
  100. break;
  101. }
  102. }
  103. fclose($ws_file);
  104. echo $title."
    ";
  105. //Move the pointer of the file
  106. //ftell()
  107. Return the current position of the pointer
  108. //fseek()
  109. Move the pointer to the specified Position
  110. //rewind()
  111. Move the pointer to the beginning of the file
  112. $fp=fopen("data.txt","r") or die("File opening failed");
  113. //Open the file in read-only mode
  114. echo ftell($fp)."
    ";
  115. //Output the position of the pointer when the file was just opened. The default is 0
  116. echo fread($fp,10)."
    ";
  117. // After reading the first 10 characters of the file, the file pointer has changed
  118. echo ftell($fp)."
    ";
  119. //After reading the first 10 characters of the file, the file pointer has reached position 10
  120. fseek ($fp,30,SEEK_CUR);
  121. //Move the file pointer backward 30 characters
  122. echo ftell($fp)."
    ";
  123. //After moving the file 30 characters, it reaches 40 Position
  124. echo fread($fp,10)."
    ";
  125. //Read characters between 40 and 50, the pointer will reach 50
  126. fseek($fp,-10,SEEK_END);
  127. // Set the pointer to the 10th position from the bottom of the file
  128. echo fread($fp,10)."
    ";
  129. //Output the last 10 characters of the file
  130. rewind($fp);
  131. //Set the file pointer To the beginning of the file
  132. echo ftell($fp);
  133. //The file pointer returns to the beginning, so 0
  134. fclose($fp);
  135. ?>
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