PyQt文本文件读写
作者：互联网
1 ## ==============自定义功能函数========================
2 def __openByIODevice(self,fileName): ##用QFile打开文件
3 fileDevice=QFile(fileName)
4 # print("**",fileDevice.exists())
5 # print("@@",fileDevice.open(QIODevice.ReadOnly | QIODevice.Text))
6 if not fileDevice.exists(): #判断文件是否存在
7 return False
8 if not fileDevice.open(QIODevice.ReadOnly | QIODevice.Text):
9 return False
10 try:
11 self.ui.textEdit.clear()
12 while not fileDevice.atEnd():
13 qtBytes = fileDevice.readLine() #返回QByteArray类型
14 pyBytes = bytes(qtBytes.data()) #将QByteArray转换为bytes类型
15 lineStr = pyBytes.decode("utf-8") #bytes转换为str类型
16 lineStr = lineStr.strip() #去除结尾增加的空行
17 self.ui.textEdit.appendPlainText(lineStr)
18 finally:
19 fileDevice.close()
20 return True
21 pass
22
23
24 def __saveByIODevice(self,fileName): ##用QFile保存文件
25 fileDevice=QFile(fileName)
26 if not fileDevice.open(QIODevice.WriteOnly | QIODevice.Text):
27 return False
28 try:
29 text=self.ui.textEdit.toPlainText()
30 strBytes=text.encode("utf-8")
31 fileDevice.write(strBytes)
32 finally:
33 fileDevice.close()
34 return True
35 pass
36
37
38 def __openByStream(self,fileName): ##用QTextStream打开文件
39 fileDevice=QFile(fileName)
40 if not fileDevice.exists(): #判断文件是否存在
41 return False
42 if not fileDevice.open(QIODevice.ReadOnly | QIODevice.Text):
43 return False
44 try:
45 fileStream=QTextStream(fileDevice)
46 fileStream.setAutoDetectUnicode(True) #自动检测Unicode
47 fileStream.setCodec("utf-8")
48 self.ui.textEdit.clear()
49 while not fileStream.atEnd():
50 lineStr=fileStream.readLine() #读取文件的一行读取出来的就是str
51 self.ui.textEdit.appendPlainText(lineStr) #添加到文本框显示
52 finally:
53 fileDevice.close()
54 return True
55 pass
56
57
58 def __saveByStream(self,fileName): ##用 QTextStream 保存文件
59 fileDevice=QFile(fileName)
60 if not fileDevice.open(QIODevice.WriteOnly | QIODevice.Text):
61 return False
62 try:
63 fileStream=QTextStream(fileDevice)
64 fileStream.setAutoDetectUnicode(True) #自动检测Unicode
65 fileStream.setCodec("utf-8")
66 text=self.ui.textEdit.toPlainText()
67 fileStream<<text
68 fileStream<<"\n************在尾部添加的第一行"
69 finally:
70 fileDevice.close()
71 return True
72 pass
73
74
75 ## ==============event处理函数==========================
76
77
78 ## ==========由connectSlotsByName()自动连接的槽函数============
79
80 @pyqtSlot() ##用QFile 打开文件
81 def on_actQFile_Open_triggered(self):
82 curPath=QDir.currentPath()
83 title="打开一个文件"
84 filt="程序文件(*.h*.cpp*.py);;文本文件(*.txt);;所有文件(*.*)"
85 fileName,flt=QFileDialog.getOpenFileName(self,title,curPath,filt)
86 if fileName == "":
87 return
88 if self.__openByIODevice(fileName):
89 self.ui.statusBar.showMessage(fileName)
90 else:
91 QMessageBox.critical(self,"错误","打开文件失败")
92 pass
93
94
95 @pyqtSlot() ##用QFile 另存文件
96 def on_actQFile_Save_triggered(self):
97 curPath=QDir.currentPath()
98 title="另存为一个文件"
99 filt="Python程序(*.py);;C++程序(*.h*.cpp);;所有文件(*.*)"
100 fileName,flt=QFileDialog.getSaveFileName(self,title,curPath,filt)
101 if fileName == "":
102 return
103 if self.__saveByIODevice(fileName):
104 self.ui.statusBar.showMessage(fileName)
105 else:
106 QMessageBox.critical(self,"错误","保存文件失败")
107 pass
108
109
110 @pyqtSlot() ##用QTextStream 打开文件
111 def on_actStream_Open_triggered(self):
112 curPath=QDir.currentPath()
113 title="打开一个文件"
114 filt="程序文件(*.h*.cpp*.py);;文本文件(*.txt);;所有文件(*.*)"
115 fileName,flt=QFileDialog.getOpenFileName(self,title,curPath,filt)
116 if fileName == "":
117 return
118 if self.__openByStream(fileName):
119 self.ui.statusBar.showMessage(fileName)
120 else:
121 QMessageBox.critical(self,"错误","打开文件失败")
122 pass
123
124
125 @pyqtSlot() ##用QTextStream 另存文件
126 def on_actStream_Save_triggered(self):
127 curPath=QDir.currentPath()
128 title="另存为一个文件"
129 filt="Python程序(*.py);;C++程序(*.h*.cpp);;所有文件(*.*)"
130 fileName,flt=QFileDialog.getSaveFileName(self,title,curPath,filt)
131 if fileName == "":
132 return
133 if self.__saveByStream(fileName):
134 self.ui.statusBar.showMessage(fileName)
135 else:
136 QMessageBox.critical(self,"错误","保存文件失败")
137 pass
138
139
140 @pyqtSlot() ##用 python 的file()打开文件
141 def on_actPY_Open_triggered(self):
142 curPath=QDir.currentPath()
143 title="打开一个文件"
144 filt="程序文件(*.h*.cpp*.py);;文本文件(*.txt);;所有文件(*.*)"
145 fileName,flt=QFileDialog.getOpenFileName(self,title,curPath,filt)
146 if fileName == "":
147 return
148 self.ui.textEdit.clear()
149 fileDevice=open(fileName,mode='r',encoding='utf-8')
150 try:
151 for eachLine in fileDevice: #每次读取一行
152 lineStr = eachLine.strip()
153 self.ui.textEdit.appendPlainText(lineStr)
154 self.ui.statusBar.showMessage(fileName)
155 finally:
156 fileDevice.close()
157 pass
158
159
160 @pyqtSlot() ##用 python的file() 保存文件
161 def on_actPY_Save_triggered(self):
162 curPath=QDir.currentPath()
163 title="另存为一个文件"
164 filt="Python程序(*.py);;C++程序(*.h*.cpp);;所有文件(*.*)"
165 fileName,flt=QFileDialog.getSaveFileName(self,title,curPath,filt)
166 if fileName == "":
167 return
168 text=self.ui.textEdit.toPlainText() #str类型
169 fileDevice=open(fileName,mode='w',encoding='utf-8')
170 try:
171 fileDevice.write(text)
172 self.ui.statusBar.showMessage(fileName)
173 finally:
174 fileDevice.close()
175 pass
标签：fileDevice,return,fileStream,读写,PyQt,fileName,文本文件,QIODevice,self 来源： https://www.cnblogs.com/sforstudy/p/15944137.html