JAVA 創建TXT文件，寫入文件內容，讀取文件內容 .
分類： jse 2012-05-18 22:20 28820人閱讀 評論(2) 收藏 舉報
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01.package com.abin.facade.ws.mail.function;
02.
03.import java.io.BufferedReader;
04.import java.io.File;
05.import java.io.FileOutputStream;
06.import java.io.FileReader;
07.import java.io.RandomAccessFile;
08.
09.public class FileOperation {
10.
11. /**
12. * 創建文件
13. * @param fileName
14. * @return
15. */
16. public static boolean createFile(File fileName)throws Exception{
17. boolean flag=false;
18. try{
19. if(!fileName.exists()){
20. fileName.createNewFile();
21. flag=true;
22. }
23. }catch(Exception e){
24. e.printStackTrace();
25. }
26. return true;
27. }
28.
29. /**
30. * 讀TXT文件內容
31. * @param fileName
32. * @return
33. */
34. public static String readTxtFile(File fileName)throws Exception{
35. String result=null;
36. FileReader fileReader=null;
37. BufferedReader bufferedReader=null;
38. try{
39. fileReader=new FileReader(fileName);
40. bufferedReader=new BufferedReader(fileReader);
41. try{
42. String read=null;
43. while((read=bufferedReader.readLine())!=null){
44. result=result+read+"\r\n";
45. }
46. }catch(Exception e){
47. e.printStackTrace();
48. }
49. }catch(Exception e){
50. e.printStackTrace();
51. }finally{
52. if(bufferedReader!=null){
53. bufferedReader.close();
54. }
55. if(fileReader!=null){
56. fileReader.close();
57. }
58. }
59. System.out.println("讀取出來的文件內容是："+"\r\n"+result);
60. return result;
61. }
62.
63.
64. public static boolean writeTxtFile(String content,File fileName)throws Exception{
65. RandomAccessFile mm=null;
66. boolean flag=false;
67. FileOutputStream o=null;
68. try {
69. o = new FileOutputStream(fileName);
70. o.write(content.getBytes("GBK"));
71. o.close();
72.// mm=new RandomAccessFile(fileName,"rw");
73.// mm.writeBytes(content);
74. flag=true;
75. } catch (Exception e) {
76. // TODO: handle exception
77. e.printStackTrace();
78. }finally{
79. if(mm!=null){
80. mm.close();
81. }
82. }
83. return flag;
84. }
85.
86.
87.
88.public static void contentToTxt(String filePath, String content) {
89. String str = new String(); //原有txt內容
90. String s1 = new String();//內容更新
91. try {
92. File f = new File(filePath);
93. if (f.exists()) {
94. System.out.print("文件存在");
95. } else {
96. System.out.print("文件不存在");
97. f.createNewFile();// 不存在則創建
98. }
99. BufferedReader input = new BufferedReader(new FileReader(f));
100.
101. while ((str = input.readLine()) != null) {
102. s1 += str + "\n";
103. }
104. System.out.println(s1);
105. input.close();
106. s1 += content;
107.
108. BufferedWriter output = new BufferedWriter(new FileWriter(f));
109. output.write(s1);
110. output.close();
111. } catch (Exception e) {
112. e.printStackTrace();
113.
114. }
115. }
116.
117.}
