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Home Backend Development PHP Tutorial Basic operations on PHP files

Basic operations on PHP files

Jul 25, 2016 am 08:42 AM
  2. //Basic file operations
  3. //fopen()
  4. Open a file
  5. //Open a file using an absolute path, select read-only mode, and return the resource $handle
  6. $handle= fopen("D:/lamp/apache2/htdocs/test/file.txt","r");
  7. //Access files in the document root directory and also select read-only mode
  8. $handle=fopen($_SERVER[' DOCUMENT_ROOT']."/test/file.txt","r");
  9. //Open remote files, which can only be opened in read mode using the http protocol
  10. $handle=fopen("http://www.wowsai. com","r");
  11. //Use FTP protocol to open remote files. If the FTP server is writable, it can be opened in write mode
  12. //$handle=fopen("ftp://user:password@example. com/file.txt",'w');
  13. //fclose()
  14. Close the open resource type
  15. //fwrite()
  16. Write content to the file
  17. $fileName="data.txt";
  18. // Declare a file variable
  19. //Open the file in write-only mode, create it if it does not exist, and pass the program when the opening fails
  20. $f_handle=fopen("data.txt","w")or die("Open< b>".$fileName."File failed");
  21. for($i=0;$i<10;$i++){
  22. //Add content to the file through a loop
  23. fwrite ($f_handle,"againn");
  24. }
  25. fclose($f_handle);
  26. //Close the open file
  27. //file_put_contents()
  28. Write all data to the specified file at once
  29. //Read the file content
  30. //fread()
  31. Read an open file
  32. //file_get_contents()
  33. Read a file into a string
  34. //fgets()
  35. Return a line from an open file
  36. //fgetc()
  37. From an open file Return characters in
  38. //file()
  39. Read the file into an array
  40. //readfile()
  41. Read a file and output it to the output buffer
  42. //feof()
  43. Judge whether a file pointer is at the end of the file At
  44. //Read the specified number of bytes from the file and store it in a variable
  45. $fileName2="data.txt";
  46. $f_hand=fopen($fileName2,"r")or die("Open the file Failed");
  47. $contents=fread($f_hand,50);
  48. fclose($f_hand);
  49. echo $contents."
    ";
  50. //Read all the contents from the file and store them in a variable , read part of it each time, read in a loop
  51. /* $fileName3="D:/lamp/apache2/icons/link.gif";
  52. //Save the file name of the binary file into a variable
  53. $f3_handle= fopen($fileName3,"rb")or die("File opening failed"); //Open the file in read-only mode, the mode is added with "b"
  54. $f3_contents="";
  55. //Declare one for saving String of file content
  56. while(!feof($f3_handle)){
  57. //Loop to read the contents of the file until the end of the file
  58. $f3_contents.=fread($f3_handle,1024);
  59. //Read each time 1024 characters
  60. }
  61. fclose($f3_handle);
  62. echo $f3_contents; */
  63. //Another way to read the entire contents of the file
  64. $fileName4="data.txt";
  65. $f4_handle=fopen($fileName4 ,"r")or die("File opening failed");
  66. $f4_con=fread($f4_handle,filesize($fileName4));
  67. //Use filesize to get the length of the file, so as to read the entire content of the file
  68. fclose($f4_handle);
  69. echo $f4_con."
    ";
  70. //Another method to read the entire contents of the file, which has much better performance than the above
  71. echo file_get_contents("data.txt");
  72. $f5_handle=fopen("data.txt","r") or die("File opening failed");
  73. while(!feof($f5_handle)){
  74. //Determine whether the pointer reaches the end of the file
  75. $buffer= fgets($f5_handle);
  76. //Read one line from the file at a time
  77. echo $buffer."
    ";
  78. }
  79. fclose($f5_handle);
  80. $f6_handle=fopen("data.txt", "r") or die("File opening failed");
  81. while(!feof($f6_handle)){
  82. //Judge whether the pointer reaches the end of the file
  83. $buffer=fgetc($f6_handle);
  84. //Every time from Read a character from the file
  85. echo $buffer."
    ";
  86. }
  87. fclose($f6_handle);
  88. print_r(file("data.txt"));
  89. //Read the file into an array
  90. readfile("data.txt");
  91. //Read the contents of the file directly and output it to the browser
  92. //Access remote files
  93. Make sure "allow_url_fopen" in php.ini is turned on, and make sure The remote file has access permission
  94. $ws_file=fopen("http://www.wowsai.com","r")or die("Remote file opening failed");
  95. //Open the remote file
  96. while(!feof( $ws_file)){
  97. $ws_line=fgets($ws_file);
  98. if(preg_match("/(.*)/",$ws_line,$res)){
  99. //Use Regularly matches the title of the website
  100. $title=$res[1];
  101. break;
  102. }
  103. }
  104. fclose($ws_file);
  105. echo $title."
    ";
  106. //Move the pointer of the file
  107. //ftell()
  108. Return the current position of the pointer
  109. //fseek()
  110. Move the pointer to the specified Position
  111. //rewind()
  112. Move the pointer to the beginning of the file
  113. $fp=fopen("data.txt","r") or die("File opening failed");
  114. //Open the file in read-only mode
  115. echo ftell($fp)."
    ";
  116. //Output the position of the pointer when the file was just opened. The default is 0
  117. echo fread($fp,10)."
    ";
  118. // After reading the first 10 characters of the file, the file pointer has changed
  119. echo ftell($fp)."
    ";
  120. //After reading the first 10 characters of the file, the file pointer has reached position 10
  121. fseek ($fp,30,SEEK_CUR);
  122. //Move the file pointer backward 30 characters
  123. echo ftell($fp)."
    ";
  124. //After moving the file 30 characters, it reaches 40 Position
  125. echo fread($fp,10)."
    ";
  126. //Read characters between 40 and 50, the pointer will reach 50
  127. fseek($fp,-10,SEEK_END);
  128. // Set the pointer to the 10th position from the bottom of the file
  129. echo fread($fp,10)."
    ";
  130. //Output the last 10 characters of the file
  131. rewind($fp);
  132. //Set the file pointer To the beginning of the file
  133. echo ftell($fp);
  134. //The file pointer returns to the beginning, so 0
  135. fclose($fp);
  136. ?>
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