PyQt5 QTextEdit按钮功能实现：删除空行与文本前后缀添加

Hey there, I've put together a complete working example that implements both of your requested features in the btn_func function. Let's dive in:

Full Code Implementation #

import sys
from PyQt5.QtWidgets import (QApplication, QMainWindow, QTextEdit, 
                             QPushButton, QVBoxLayout, QWidget, QRadioButton, QHBoxLayout)

class TextEditorWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.initUI()
        
    def initUI(self):
        self.setWindowTitle("Text Editor Tool")
        self.setGeometry(100, 100, 600, 400)
        
        # Central widget and main layout
        central_widget = QWidget()
        self.setCentralWidget(central_widget)
        main_layout = QVBoxLayout(central_widget)
        
        # Text edit area
        self.text_edit = QTextEdit()
        main_layout.addWidget(self.text_edit)
        
        # Radio buttons for prefix/suffix choice
        radio_layout = QHBoxLayout()
        self.radio_prefix = QRadioButton("Add prefix '12'")
        self.radio_suffix = QRadioButton("Add suffix '12'")
        # Default to suffix option
        self.radio_suffix.setChecked(True)
        radio_layout.addWidget(self.radio_prefix)
        radio_layout.addWidget(self.radio_suffix)
        main_layout.addLayout(radio_layout)
        
        # Process button
        self.process_btn = QPushButton("Process Text")
        self.process_btn.clicked.connect(self.btn_func)
        main_layout.addWidget(self.process_btn)
        
    def btn_func(self):
        # Get current text from QTextEdit
        original_text = self.text_edit.toPlainText()
        if not original_text:
            return
        
        # Step 1: Remove all empty lines (including lines with only whitespace)
        lines = original_text.split('\n')
        filtered_lines = [line for line in lines if line.strip() != '']
        
        # Step 2: Add prefix or suffix '12' to each line
        processed_lines = []
        for line in filtered_lines:
            if self.radio_prefix.isChecked():
                processed_line = f"12{line}"
            else:
                processed_line = f"{line}12"
            processed_lines.append(processed_line)
        
        # Combine lines back into a single string and set back to QTextEdit
        final_text = '\n'.join(processed_lines)
        self.text_edit.setPlainText(final_text)

if __name__ == "__main__":
    app = QApplication(sys.argv)
    window = TextEditorWindow()
    window.show()
    sys.exit(app.exec_())

How It Works #

1. Removing Empty Lines #

• First, we pull the plain text from the QTextEdit using toPlainText()
• Split the text into individual lines with split('\n')
• Use a list comprehension to filter out lines that are empty (or only contain spaces/tabs) — checking line.strip() != '' covers both truly blank lines and lines with invisible whitespace

2. Adding Prefix/Suffix '12' #

• I added two radio buttons to let the user pick between prefix or suffix (you can hardcode this to one option if you don't need user choice)
• Loop through the filtered lines (after removing empty ones)
• Depending on which radio button is selected, we either prepend '12' to the line or append it
• Finally, we join all processed lines back into a single string with '\n'.join() and update the QTextEdit with the result

Quick Notes #

• The function handles empty lines first, then applies the prefix/suffix — this avoids wasting time modifying lines we're just going to delete anyway
• If the QTextEdit is empty, the function exits early to skip unnecessary processing

内容的提问来源于stack exchange，提问作者Jack Parten