問題描述

這是一個關于輸入驗證的兩部分問題，其中包含一個特定組件和另一個更通用的組件.

This is a two part question about input validation with one specific and another more general component.

具體:

在研究該主題時，我發現 THIS on Regular表達式.我意識到這篇文章中的代碼使用的是 PyQt4.但是我想讓它與 PyQt5 一起工作，因為我已經用它開始了我的項目.(顯然是盲目的——我只能找到它的 C++ 文檔)

While researching the topic, I found THIS on Regular Expressions. I realize that the code in this post is using PyQt4. However I wanted to get this working with PyQt5, since I had already started my project with it. (Obviously blindly - I can only find C++ documentation for it)

這是我嘗試過的:

# somewhere above:     
self.le_input = QtWidgets.QLineEdit()

# at some point validate_input gets called:
# more on that in the second part of this question

def validate_input(self):
    reg_ex = QtCore.QRegExp(""[0-9]+.?[0-9]{,2}"")
    input_validator = QtGui.QRegExpValidator(reg_ex, self.le_input.text())
    self.le_input.setValidator(input_validator)

當我運行代碼時，出現以下錯誤:

When I run the code I get the following Error:

QRegExpValidator(parent: QObject = None): 參數 1 具有意外類型 'QRegExp'QRegExpValidator(QRegExp, parent: QObject = None): 參數 2 具有意外類型 'str'

QRegExpValidator(parent: QObject = None): argument 1 has unexpected type 'QRegExp' QRegExpValidator(QRegExp, parent: QObject = None): argument 2 has unexpected type 'str'

這些不正是需要的參數嗎?有誰知道如何讓這個工作?

Aren't these exactly the required arguments? Does anyone know how to get this working?

將軍:

在 Python 中使用 PyQt 實現實時驗證的有效方法是什么?

What is an effective way to implement live validation with PyQt in Python?

目前我會使用:

self.le_input.textChanged.connect(self.validate_input)

這確實有效，但是一旦我嘗試將兩個相互影響的 QtLineEdits 連接到同一個插槽，事情就會停止工作，因為它們同時調用了textChanged".

This does work, but as soon as I try to connect two QtLineEdits, that affect each other, to the same slot, things stop working because "textChanged" gets called by both of them at the same time.

用例:兩個輸入字段:Amount before TAX 和 Amount after TAX - 輸入時自動填充另一個字段.

Use case: Two input fields: Amount before TAX and Amount after TAX - and whichever you enter automatically fills the other one while typing.

先驗證，再計算，再輸出到其他字段.

First validation, then calculation, then output to the other field.

提前非常感謝！非常感謝任何幫助！

推薦答案

你可以為不同的QLineEdit對象設置不同的驗證器.

You can set different validators for different QLineEdit objects.

QRegExpValidator 有兩個構造函數:

QRegExpValidator(parent: QObject = None)
QRegExpValidator(QRegExp, parent: QObject = None)

所以，您應該將代碼更改為:

so, you should change your code to:

reg_ex = QRegExp("[0-9]+.?[0-9]{,2}")
input_validator = QRegExpValidator(reg_ex, self.le_input)
self.le_input.setValidator(input_validator)

一旦為 QLineEdit 設置了驗證器，就不需要使用了

Once you set validator for QLineEdit, there is no need to use

self.le_input.textChanged.connect(self.validate_input)

刪除即可.這應該可以正常工作.

Just delete it. And that should work fine.

如果您想查找有關 PyQt5 的文檔，您可以在控制臺中簡單地使用它:

If you want to find documentation about PyQt5, you can simple use this in your console:

pydoc3 PyQt5.QtGui.QRegExpValidator

但是 pydoc 只能顯示很少的信息，所以你也應該使用 C++ 版本的文檔.

But pydoc can only show you little information, so you should use C++ version documation as well.

最后，舉個例子:

from PyQt5.Qt import QApplication
from PyQt5.QtCore import QRegExp
from PyQt5.QtGui import QRegExpValidator
from PyQt5.QtWidgets import QWidget, QLineEdit

import sys

class MyWidget(QWidget):
    def __init__(self, parent=None):
        super(QWidget, self).__init__(parent)
        self.le_input = QLineEdit(self)

        reg_ex = QRegExp("[0-9]+.?[0-9]{,2}")
        input_validator = QRegExpValidator(reg_ex, self.le_input)
        self.le_input.setValidator(input_validator)

if __name__ == '__main__':
    a = QApplication(sys.argv)

    w = MyWidget()
    w.show()

    a.exec()

這篇關于PyQt5 和 Python 中的用戶輸入驗證的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！