pyqt5 文件读写

### PyQt5 文件读写操作 #### 文本文件读取与保存 为了执行文本文件的读取和保存，在PyQt5中可以利用`QFileDialog`来获取文件路径，并使用Python标准库中的方法来进行实际的数据处理[^1]。 对于简单的文本文件读取，可以通过如下方式实现： ```python from PyQt5.QtWidgets import QApplication, QMainWindow, QTextEdit, QAction, QFileDialog import sys class TextEditor(QMainWindow): def __init__(self): super().__init__() text_edit = QTextEdit() self.setCentralWidget(text_edit) open_action = QAction('Open', self) open_action.triggered.connect(self.open_file_dialog) save_action = QAction('Save', self) save_action.triggered.connect(self.save_file_dialog) menubar = self.menuBar() file_menu = menubar.addMenu('&File') file_menu.addAction(open_action) file_menu.addAction(save_action) def open_file_dialog(self): options = QFileDialog.Options() filename, _ = QFileDialog.getOpenFileName( self, "Choose a file", "", "All Files (*);;Text Files (*.txt)", options=options ) if filename: with open(filename, 'r') as f: content = f.read() # Read the entire contents of the file at once. self.centralWidget().setText(content) # Set this to your widget that displays data. def save_file_dialog(self): options = QFileDialog.Options() filename, _ = QFileDialog.getSaveFileName( self, "Save File As...", "", "Text Files (*.txt);;All Files (*)", options=options ) if filename: with open(filename, 'w') as f: f.write(self.centralWidget().toPlainText()) if __name__ == '__main__': app = QApplication(sys.argv) editor = TextEditor() editor.show() sys.exit(app.exec_()) ``` 这段代码展示了如何创建一个简易的文字编辑器，它允许用户打开并查看`.txt`类型的文档以及将当前的内容另存为新的文本文件。 #### Excel 文件读写 当涉及到Excel文件的操作时，则可借助于第三方库pandas配合`QTableView`组件完成数据表格形式的显示与修改。下面是一个简化版的例子说明怎样连接Excel文件至GUI界面以便浏览其内容[^5]。 ```python from PyQt5.QtWidgets import QApplication, QMainWindow, QPushButton, QVBoxLayout, QWidget, QTableView from PyQt5.QtCore import Qt import pandas as pd from PyQt5.QtGui import QStandardItemModel, QStandardItem class SpreadsheetViewer(QMainWindow): def __init__(self): super().__init__() layout = QVBoxLayout() button_open_excel = QPushButton("Open Excel", self) button_open_excel.clicked.connect(self.load_excel_data) self.table_view = QTableView() container_widget = QWidget() container_widget.setLayout(layout) layout.addWidget(button_open_excel) layout.addWidget(self.table_view) self.setCentralWidget(container_widget) def load_excel_data(self): excel_path, _ = QFileDialog.getOpenFileName(None,"Select an Excel file","","Excel files (*.xlsx *.xls)") if not excel_path: return df = pd.read_excel(excel_path) model = QStandardItemModel(len(df.index),len(df.columns)) model.setHorizontalHeaderLabels(df.columns.values.tolist()) for row in range(len(df.index)): for column in range(len(df.columns)): item = QStandardItem(str(df.iat[row,column])) model.setItem(row, column, item) self.table_view.setModel(model) if __name__ == "__main__": application = QApplication([]) window = SpreadsheetViewer() window.setWindowTitle("Spreadsheet Viewer") window.resize(800,600) window.show() exit(application.exec_()) ``` 此段脚本实现了基本的功能——即让用户可以选择本地磁盘上的Excel工作簿，并将其转换成可以在界面上滚动查看的形式。