如何在PyQt4的QTextEdit中獲取光標旁邊的文本

Question

我正在為bash腳本制作一個輕量級的IDE，我想要一個選項，當我按Ctrl + / >>一行時，“ textCursor”所在的位置將被注釋，而我設法做到了，但是我也想要用相同的命令取消注釋行。 但是我無法在“ textCursor”旁邊獲取文本。

def commentShortcut(self):
    cursor = self.textCursor()
    Y = cursor.blockNumber()
    self.moveCursor(QtGui.QTextCursor.End)
    cursor = QtGui.QTextCursor(self.document().findBlockByLineNumber(Y))
    self.setTextCursor(cursor)
    self.insertPlainText("#")

這部分代碼將我的textCursor移動到該行的開頭，在此行中我使用self.insertPlainText（）函數插入了“＃”（注釋符號）。

注意：class繼承了QTextEdit ，這就是為什么我僅將它與self一起使用 。

綜上所述，我只需要一種方法來檢查textCursor旁邊的字符，如果該字符為“＃”，我將其刪除，如果不是，則將插入新的“＃”，將不勝感激。

Answer 1

您必須移至該行的開頭，然后跳過空格，選擇第一個字符並進行比較，然后對於刪除過程，您必須刪除"#"和右邊的空格，對於插入，它是建議插入"# "

附言 ：我無法嘗試使用快捷鍵Ctrl + /來使用： Ctrl + R

import sys
from PyQt4 import QtCore, QtGui

class TextEdit(QtGui.QTextEdit):
    def __init__(self, *args, **kwargs):
        QtGui.QWidget.__init__(self, *args, **kwargs)
        shortcut = QtGui.QShortcut(QtGui.QKeySequence("Ctrl+R"), self)
        shortcut.activated.connect(self.commentShortcut)

    def commentShortcut(self):
        pos = self.textCursor().position()
        self.moveCursor(QtGui.QTextCursor.StartOfLine)
        line_text = self.textCursor().block().text()
        if self.textCursor().block().text().startswith(" "):
            # skip the white space
            self.moveCursor(QtGui.QTextCursor.NextWord)
        self.moveCursor(QtGui.QTextCursor.NextCharacter,QtGui.QTextCursor.KeepAnchor)
        character = self.textCursor().selectedText()
        if character == "#":
            # delete #
            self.textCursor().deletePreviousChar()
            # delete white space 
            self.moveCursor(QtGui.QTextCursor.NextWord,QtGui.QTextCursor.KeepAnchor)
            self.textCursor().removeSelectedText()
        else:
            self.moveCursor(QtGui.QTextCursor.PreviousCharacter,QtGui.QTextCursor.KeepAnchor)
            self.textCursor().insertText("# ")
        cursor = QtGui.QTextCursor(self.textCursor())
        cursor.setPosition(pos)
        self.setTextCursor(cursor)


if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    w = TextEdit()
    w.append('''

#!/bin/bash
# Simple line count example, using bash
#
# Bash tutorial: http://linuxconfig.org/Bash_scripting_Tutorial#8-2-read-file-into-bash-array
# My scripting link: http://www.macs.hw.ac.uk/~hwloidl/docs/index.html#scripting
#
# Usage: ./line_count.sh file
# -----------------------------------------------------------------------------

# Link filedescriptor 10 with stdin
exec 10<&0
# stdin replaced with a file supplied as a first argument
exec < $1
# remember the name of the input file
in=$1

# init
file="current_line.txt"
let count=0

# this while loop iterates over all lines of the file
while read LINE
do
    # increase line counter 
    ((count++))
    # write current line to a tmp file with name $file (not needed for counting)
    echo $LINE > $file
    # this checks the return code of echo (not needed for writing; just for demo)
    if [ $? -ne 0 ] 
     then echo "Error in writing to file ${file}; check its permissions!"
    fi
done

echo "Number of lines: $count"
echo "The last line of the file is: `cat ${file}`"

# Note: You can achieve the same by just using the tool wc like this
echo "Expected number of lines: `wc -l $in`"

# restore stdin from filedescriptor 10
# and close filedescriptor 10
exec 0<&10 10<&-
        ''')
    w.show()
    sys.exit(app.exec_())