python3+PyQt5泛型委託詳解
這篇文章主要為大家詳細介紹了python3 PyQt5泛型委託的相關資料,具有一定的參考價值,感興趣的小伙伴們可以參考一下
自訂委託可以讓我們對視圖中出現的資料項的外觀和行為進行完全控制。如果有很多模型,可能會希望不是全部的大多數模型能夠僅用一個自訂委託,如果不能這麼做,那麼對於這些自訂委託,將很有可能存在大量重複程式碼。為了使得維護工作變得輕鬆,更好的方法為不要為每個模型建立自訂委託,而是用一系列的通用元件來共同構成一個委託。本文透過Python3 pyqt5實現了python Qt GUI 快速編程的16章的泛型委託例子。
/home/yrd/eric_workspace/chap16/richtextlineedit.py
#!/usr/bin/env python3 import platform import sys import html from PyQt5.QtCore import QSize, Qt,pyqtSignal from PyQt5.QtGui import QColor, QFont,QFontMetrics, QIcon, QKeySequence, QPixmap,QTextCharFormat from PyQt5.QtWidgets import QAction,QApplication,QMenu,QTextEdit class RichTextLineEdit(QTextEdit): returnPressed=pyqtSignal() (Bold, Italic, Underline, StrikeOut, Monospaced, Sans, Serif, NoSuperOrSubscript, Subscript, Superscript) = range(10) def __init__(self, parent=None): super(RichTextLineEdit, self).__init__(parent) self.monofamily = "courier" self.sansfamily = "helvetica" self.seriffamily = "times" self.setLineWrapMode(QTextEdit.NoWrap) self.setTabChangesFocus(True) self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff) self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff) fm = QFontMetrics(self.font()) h = int(fm.height() * (1.4 if platform.system() == "Windows" else 1.2)) self.setMinimumHeight(h) self.setMaximumHeight(int(h * 1.2)) self.setToolTip("Press <b>Ctrl+M</b> for the text effects " "menu and <b>Ctrl+K</b> for the color menu") def toggleItalic(self): self.setFontItalic(not self.fontItalic()) def toggleUnderline(self): self.setFontUnderline(not self.fontUnderline()) def toggleBold(self): self.setFontWeight(QFont.Normal if self.fontWeight() > QFont.Normal else QFont.Bold) def sizeHint(self): return QSize(self.document().idealWidth() + 5, self.maximumHeight()) def minimumSizeHint(self): fm = QFontMetrics(self.font()) return QSize(fm.width("WWWW"), self.minimumHeight()) def contextMenuEvent(self, event): self.textEffectMenu() def keyPressEvent(self, event): if event.modifiers() & Qt.ControlModifier: handled = False if event.key() == Qt.Key_B: self.toggleBold() handled = True elif event.key() == Qt.Key_I: self.toggleItalic() handled = True elif event.key() == Qt.Key_K: self.colorMenu() handled = True elif event.key() == Qt.Key_M: self.textEffectMenu() handled = True elif event.key() == Qt.Key_U: self.toggleUnderline() handled = True if handled: event.accept() return if event.key() in (Qt.Key_Enter, Qt.Key_Return): self.returnPressed.emit() event.accept() else: QTextEdit.keyPressEvent(self, event) def colorMenu(self): pixmap = QPixmap(22, 22) menu = QMenu("Colour") for text, color in ( ("&Black", Qt.black), ("B&lue", Qt.blue), ("Dark Bl&ue", Qt.darkBlue), ("&Cyan", Qt.cyan), ("Dar&k Cyan", Qt.darkCyan), ("&Green", Qt.green), ("Dark Gr&een", Qt.darkGreen), ("M&agenta", Qt.magenta), ("Dark Mage&nta", Qt.darkMagenta), ("&Red", Qt.red), ("&Dark Red", Qt.darkRed)): color = QColor(color) pixmap.fill(color) action = menu.addAction(QIcon(pixmap), text, self.setColor) action.setData(color) self.ensureCursorVisible() menu.exec_(self.viewport().mapToGlobal( self.cursorRect().center())) def setColor(self): action = self.sender() if action is not None and isinstance(action, QAction): color = QColor(action.data()) if color.isValid(): self.setTextColor(color) def textEffectMenu(self): format = self.currentCharFormat() menu = QMenu("Text Effect") for text, shortcut, data, checked in ( ("&Bold", "Ctrl+B", RichTextLineEdit.Bold, self.fontWeight() > QFont.Normal), ("&Italic", "Ctrl+I", RichTextLineEdit.Italic, self.fontItalic()), ("Strike &out", None, RichTextLineEdit.StrikeOut, format.fontStrikeOut()), ("&Underline", "Ctrl+U", RichTextLineEdit.Underline, self.fontUnderline()), ("&Monospaced", None, RichTextLineEdit.Monospaced, format.fontFamily() == self.monofamily), ("&Serifed", None, RichTextLineEdit.Serif, format.fontFamily() == self.seriffamily), ("S&ans Serif", None, RichTextLineEdit.Sans, format.fontFamily() == self.sansfamily), ("&No super or subscript", None, RichTextLineEdit.NoSuperOrSubscript, format.verticalAlignment() == QTextCharFormat.AlignNormal), ("Su&perscript", None, RichTextLineEdit.Superscript, format.verticalAlignment() == QTextCharFormat.AlignSuperScript), ("Subs&cript", None, RichTextLineEdit.Subscript, format.verticalAlignment() == QTextCharFormat.AlignSubScript)): action = menu.addAction(text, self.setTextEffect) if shortcut is not None: action.setShortcut(QKeySequence(shortcut)) action.setData(data) action.setCheckable(True) action.setChecked(checked) self.ensureCursorVisible() menu.exec_(self.viewport().mapToGlobal( self.cursorRect().center())) def setTextEffect(self): action = self.sender() if action is not None and isinstance(action, QAction): what = action.data() if what == RichTextLineEdit.Bold: self.toggleBold() return if what == RichTextLineEdit.Italic: self.toggleItalic() return if what == RichTextLineEdit.Underline: self.toggleUnderline() return format = self.currentCharFormat() if what == RichTextLineEdit.Monospaced: format.setFontFamily(self.monofamily) elif what == RichTextLineEdit.Serif: format.setFontFamily(self.seriffamily) elif what == RichTextLineEdit.Sans: format.setFontFamily(self.sansfamily) if what == RichTextLineEdit.StrikeOut: format.setFontStrikeOut(not format.fontStrikeOut()) if what == RichTextLineEdit.NoSuperOrSubscript: format.setVerticalAlignment( QTextCharFormat.AlignNormal) elif what == RichTextLineEdit.Superscript: format.setVerticalAlignment( QTextCharFormat.AlignSuperScript) elif what == RichTextLineEdit.Subscript: format.setVerticalAlignment( QTextCharFormat.AlignSubScript) self.mergeCurrentCharFormat(format) def toSimpleHtml(self): htmltext = "" black = QColor(Qt.black) block = self.document().begin() while block.isValid(): iterator = block.begin() while iterator != block.end(): fragment = iterator.fragment() if fragment.isValid(): format = fragment.charFormat() family = format.fontFamily() color = format.foreground().color() text=html.escape(fragment.text()) if (format.verticalAlignment() == QTextCharFormat.AlignSubScript): text = "<sub>{0}</sub>".format(text) elif (format.verticalAlignment() == QTextCharFormat.AlignSuperScript): text = "<sup>{0}</sup>".format(text) if format.fontUnderline(): text = "<u>{0}</u>".format(text) if format.fontItalic(): text = "<i>{0}</i>".format(text) if format.fontWeight() > QFont.Normal: text = "<b>{0}</b>".format(text) if format.fontStrikeOut(): text = "<s>{0}</s>".format(text) if color != black or family: attribs = "" if color != black: attribs += ' color="{0}"'.format(color.name()) if family: attribs += ' face="{0}"'.format(family) text = "<font{0}>{1}</font>".format(attribs,text) htmltext += text iterator += 1 block = block.next() return htmltext if __name__ == "__main__": def printout(lineedit): print(str(lineedit.toHtml())) print(str(lineedit.toPlainText())) print(str(lineedit.toSimpleHtml())) app = QApplication(sys.argv) lineedit = RichTextLineEdit() lineedit.returnPressed.connect(lambda:printout(lineedit)) lineedit.show() lineedit.setWindowTitle("RichTextEdit") app.exec_()
/home/yrd/eric_workspace/chap16/genericdelegates .py
#!/usr/bin/env python3 from PyQt5.QtCore import (QDate, QSize, Qt) from PyQt5.QtWidgets import (QApplication, QDateEdit, QLineEdit, QSpinBox, QStyledItemDelegate,QStyle) from PyQt5.QtGui import QColor,QTextDocument import richtextlineedit class GenericDelegate(QStyledItemDelegate): def __init__(self, parent=None): super(GenericDelegate, self).__init__(parent) self.delegates = {} def insertColumnDelegate(self, column, delegate): delegate.setParent(self) self.delegates[column] = delegate def removeColumnDelegate(self, column): if column in self.delegates: del self.delegates[column] def paint(self, painter, option, index): delegate = self.delegates.get(index.column()) if delegate is not None: delegate.paint(painter, option, index) else: QStyledItemDelegate.paint(self, painter, option, index) def createEditor(self, parent, option, index): delegate = self.delegates.get(index.column()) if delegate is not None: return delegate.createEditor(parent, option, index) else: return QStyledItemDelegate.createEditor(self, parent, option, index) def setEditorData(self, editor, index): delegate = self.delegates.get(index.column()) if delegate is not None: delegate.setEditorData(editor, index) else: QStyledItemDelegate.setEditorData(self, editor, index) def setModelData(self, editor, model, index): delegate = self.delegates.get(index.column()) if delegate is not None: delegate.setModelData(editor, model, index) else: QStyledItemDelegate.setModelData(self, editor, model, index) class IntegerColumnDelegate(QStyledItemDelegate): def __init__(self, minimum=0, maximum=100, parent=None): super(IntegerColumnDelegate, self).__init__(parent) self.minimum = minimum self.maximum = maximum def createEditor(self, parent, option, index): spinbox = QSpinBox(parent) spinbox.setRange(self.minimum, self.maximum) spinbox.setAlignment(Qt.AlignRight|Qt.AlignVCenter) return spinbox def setEditorData(self, editor, index): value = index.model().data(index, Qt.DisplayRole) editor.setValue(value) def setModelData(self, editor, model, index): editor.interpretText() model.setData(index, editor.value()) class DateColumnDelegate(QStyledItemDelegate): def __init__(self, minimum=QDate(), maximum=QDate.currentDate(), format="yyyy-MM-dd", parent=None): super(DateColumnDelegate, self).__init__(parent) self.minimum = minimum self.maximum = maximum self.format = format def createEditor(self, parent, option, index): dateedit = QDateEdit(parent) #dateedit=QDateTimeEdit(parent) dateedit.setDateRange(self.minimum, self.maximum) dateedit.setAlignment(Qt.AlignRight|Qt.AlignVCenter) dateedit.setDisplayFormat(self.format) dateedit.setCalendarPopup(True) return dateedit def setEditorData(self, editor, index): value = index.model().data(index, Qt.DisplayRole) #if value.isNull: editor.setDate(value) #editor.setDisplayFormat(self.format) def setModelData(self, editor, model, index): model.setData(index, editor.date()) def paint(self, painter, option, index): text = index.model().data(index, Qt.DisplayRole).toString(self.format) palette = QApplication.palette() document = QTextDocument() document.setDefaultFont(option.font) if option.state & QStyle.State_Selected: document.setHtml("<font color={0}>{1}</font>".format(palette.highlightedText().color().name(),text)) else: document.setHtml(text) painter.save() color = (palette.highlight().color() if option.state & QStyle.State_Selected else QColor(index.model().data(index, Qt.BackgroundColorRole))) painter.fillRect(option.rect, color) painter.translate(option.rect.x(), option.rect.y()) document.drawContents(painter) painter.restore() class PlainTextColumnDelegate(QStyledItemDelegate): def __init__(self, parent=None): super(PlainTextColumnDelegate, self).__init__(parent) def createEditor(self, parent, option, index): lineedit = QLineEdit(parent) return lineedit def setEditorData(self, editor, index): value = index.model().data(index, Qt.DisplayRole) editor.setText(value) def setModelData(self, editor, model, index): model.setData(index, editor.text()) class RichTextColumnDelegate(QStyledItemDelegate): def __init__(self, parent=None): super(RichTextColumnDelegate, self).__init__(parent) def paint(self, painter, option, index): text = index.model().data(index, Qt.DisplayRole) palette = QApplication.palette() document = QTextDocument() document.setDefaultFont(option.font) if option.state & QStyle.State_Selected: document.setHtml("<font color={0}>{1}</font>".format(palette.highlightedText().color().name(),text)) else: document.setHtml(text) painter.save() color = (palette.highlight().color() if option.state & QStyle.State_Selected else QColor(index.model().data(index, Qt.BackgroundColorRole))) painter.fillRect(option.rect, color) painter.translate(option.rect.x(), option.rect.y()) document.drawContents(painter) painter.restore() def sizeHint(self, option, index): text = index.model().data(index).toString() document = QTextDocument() document.setDefaultFont(option.font) document.setHtml(text) return QSize(document.idealWidth() + 5, option.fontMetrics.height()) def createEditor(self, parent, option, index): lineedit = richtextlineedit.RichTextLineEdit(parent) return lineedit def setEditorData(self, editor, index): value = index.model().data(index, Qt.DisplayRole) editor.setHtml(value) def setModelData(self, editor, model, index): model.setData(index, editor.toSimpleHtml())
#/home/yrd/eric_workspace/chap16/carhirelog.pyw
#!/usr/bin/env python3 import bisect import os import platform import sys from PyQt5.QtCore import (QAbstractTableModel, QDate, QModelIndex, QVariant, Qt,pyqtSignal) from PyQt5.QtWidgets import (QApplication, QMainWindow, QShortcut, QTableView) from PyQt5.QtGui import QKeySequence import genericdelegates (LICENSE, CUSTOMER, HIRED, MILEAGEOUT, RETURNED, MILEAGEBACK, NOTES, MILEAGE, DAYS) = range(9) class CarHireLog(object): def __init__(self, license, customer, hired, mileageout, returned=QDate(), mileageback=0, notes=""): self.license = license # plain text self.customer = customer # plain text self.hired = hired # QDate self.mileageout = mileageout # int self.returned = returned # QDate self.mileageback = mileageback # int self.notes = notes # HTML def field(self, column): if column == LICENSE: return self.license elif column == CUSTOMER: return self.customer elif column == HIRED: return self.hired elif column == MILEAGEOUT: return self.mileageout elif column == RETURNED: return self.returned elif column == MILEAGEBACK: return self.mileageback elif column == NOTES: return self.notes elif column == MILEAGE: return self.mileage() elif column == DAYS: return self.days() assert False def mileage(self): return (0 if self.mileageback == 0 else self.mileageback - self.mileageout) def days(self): return (0 if not self.returned.isValid() else self.hired.daysTo(self.returned)) def __hash__(self): return super(CarHireLog, self).__hash__() def __eq__(self, other): if self.hired != other.hired: return False if self.customer != other.customer: return False if self.license != other.license: return False return id(self) == id(other) def __lt__(self, other): if self.hired < other.hired: return True if self.customer < other.customer: return True if self.license < other.license: return True return id(self) < id(other) class CarHireModel(QAbstractTableModel): dataChanged = pyqtSignal(QModelIndex,QModelIndex) def __init__(self, parent=None): super(CarHireModel, self).__init__(parent) self.logs = [] # Generate fake data import gzip import random import string surname_data = gzip.open(os.path.join( os.path.dirname(__file__), "surnames.txt.gz")).read() surnames = surname_data.decode("utf8").splitlines() years = ("06 ", "56 ", "07 ", "57 ", "08 ", "58 ") titles = ("Ms ", "Mr ", "Ms ", "Mr ", "Ms ", "Mr ", "Dr ") notetexts = ("Returned <font color=red><b>damaged</b></font>", "Returned with <i>empty fuel tank</i>", "Customer <b>complained</b> about the <u>engine</u>", "Customer <b>complained</b> about the <u>gears</u>", "Customer <b>complained</b> about the <u>clutch</u>", "Returned <font color=darkred><b>dirty</b></font>",) today = QDate.currentDate() for i in range(250): license = [] for c in range(5): license.append(random.choice(string.ascii_uppercase)) license = ("".join(license[:2]) + random.choice(years) + "".join(license[2:])) customer = random.choice(titles) + random.choice(surnames) hired = today.addDays(-random.randint(0, 365)) mileageout = random.randint(10000, 30000) notes = "" if random.random() >= 0.2: days = random.randint(1, 21) returned = hired.addDays(days) mileageback = (mileageout + (days * random.randint(30, 300))) if random.random() > 0.75: notes = random.choice(notetexts) else: returned = QDate() mileageback = 0 log = CarHireLog(license, customer, hired, mileageout, returned, mileageback, notes) bisect.insort(self.logs, log) def rowCount(self, index=QModelIndex()): return len(self.logs) def columnCount(self, index=QModelIndex()): return 9 def data(self, index, role): if not index.isValid(): return QVariant() if role == Qt.DisplayRole: log = self.logs[index.row()] value = log.field(index.column()) if (index.column() in (MILEAGEBACK, MILEAGE, DAYS) and value == 0): return 0 return value if (role == Qt.TextAlignmentRole and index.column() not in (LICENSE, CUSTOMER, NOTES)): return QVariant(int(Qt.AlignRight|Qt.AlignVCenter)) if role == Qt.BackgroundColorRole: palette = QApplication.palette() if index.column() in (LICENSE, MILEAGE, DAYS): return QVariant(palette.alternateBase()) else: return QVariant(palette.base()) return QVariant() def setData(self, index, value, role=Qt.EditRole): if (index.isValid() and role == Qt.EditRole and index.column() not in (LICENSE, MILEAGE, DAYS)): log = self.logs[index.row()] column = index.column() if column == CUSTOMER: log.customer = value elif column == HIRED: #log.hired = value.toDate() log.hired = value elif column == MILEAGEOUT: log.mileageout = value elif column == RETURNED: #log.returned = value.toDate() log.returned = value elif column == MILEAGEBACK: log.mileageback = value elif column == NOTES: log.notes = value self.dataChanged[QModelIndex,QModelIndex].emit(index,index) return True return False def headerData(self, section, orientation, role): if role == Qt.TextAlignmentRole: if orientation == Qt.Horizontal: return QVariant(int(Qt.AlignCenter)) return QVariant(int(Qt.AlignRight|Qt.AlignVCenter)) if role != Qt.DisplayRole: return QVariant() if orientation == Qt.Horizontal: if section == LICENSE: return "License" elif section == CUSTOMER: return "Customer" elif section == HIRED: return "Hired" elif section == MILEAGEOUT: return "Mileage #1" elif section == RETURNED: return "Returned" elif section == MILEAGEBACK: return "Mileage #2" elif section == DAYS: return "Days" elif section == MILEAGE: return "Miles" elif section == NOTES: return "Notes" return section + 1 def flags(self, index): flag = QAbstractTableModel.flags(self, index) if index.column() not in (LICENSE, MILEAGE, DAYS): flag |= Qt.ItemIsEditable return flag class HireDateColumnDelegate(genericdelegates.DateColumnDelegate): def createEditor(self, parent, option, index): i = index.sibling(index.row(), RETURNED) self.maximum = i.model().data(i, Qt.DisplayRole).addDays(-1) return genericdelegates.DateColumnDelegate.createEditor( self, parent, option, index) class ReturnDateColumnDelegate(genericdelegates.DateColumnDelegate): def createEditor(self, parent, option, index): i = index.sibling(index.row(), HIRED) self.minimum = i.model().data(i, Qt.DisplayRole).addDays(1) return genericdelegates.DateColumnDelegate.createEditor( self, parent, option, index) class MileageOutColumnDelegate(genericdelegates.IntegerColumnDelegate): def createEditor(self, parent, option, index): i = index.sibling(index.row(), MILEAGEBACK) maximum = i.model().data(i, Qt.DisplayRole) self.maximum = 1000000 if maximum == 0 else maximum - 1 return genericdelegates.IntegerColumnDelegate.createEditor( self, parent, option, index) class MileageBackColumnDelegate(genericdelegates.IntegerColumnDelegate): def createEditor(self, parent, option, index): i = index.sibling(index.row(), MILEAGEOUT) self.minimum = i.model().data(i, Qt.DisplayRole) + 1 return genericdelegates.IntegerColumnDelegate.createEditor( self, parent, option, index) class MainForm(QMainWindow): def __init__(self, parent=None): super(MainForm, self).__init__(parent) model = CarHireModel(self) self.view = QTableView() self.view.setModel(model) self.view.resizeColumnsToContents() delegate = genericdelegates.GenericDelegate(self) delegate.insertColumnDelegate(CUSTOMER, genericdelegates.PlainTextColumnDelegate()) earliest = QDate.currentDate().addYears(-3) delegate.insertColumnDelegate(HIRED, HireDateColumnDelegate(earliest)) delegate.insertColumnDelegate(MILEAGEOUT, MileageOutColumnDelegate(0, 1000000)) delegate.insertColumnDelegate(RETURNED, ReturnDateColumnDelegate(earliest)) delegate.insertColumnDelegate(MILEAGEBACK, MileageBackColumnDelegate(0, 1000000)) delegate.insertColumnDelegate(NOTES, genericdelegates.RichTextColumnDelegate()) self.view.setItemDelegate(delegate) self.setCentralWidget(self.view) QShortcut(QKeySequence("Escape"), self, self.close) QShortcut(QKeySequence("Ctrl+Q"), self, self.close) self.setWindowTitle("Car Hire Logs") app = QApplication(sys.argv) form = MainForm() rect = QApplication.desktop().availableGeometry() form.resize(int(rect.width() * 0.7), int(rect.height() * 0.8)) form.move(0, 0) form.show() app.exec_()
運行結果:
#相關推薦:
python3 PyQt5實作支援多執行緒的頁面索引器應用程式
以上是python3+PyQt5泛型委託詳解的詳細內容。更多資訊請關注PHP中文網其他相關文章!

熱AI工具

Undresser.AI Undress
人工智慧驅動的應用程序,用於創建逼真的裸體照片

AI Clothes Remover
用於從照片中去除衣服的線上人工智慧工具。

Undress AI Tool
免費脫衣圖片

Clothoff.io
AI脫衣器

Video Face Swap
使用我們完全免費的人工智慧換臉工具,輕鬆在任何影片中換臉!

熱門文章

熱工具

記事本++7.3.1
好用且免費的程式碼編輯器

SublimeText3漢化版
中文版,非常好用

禪工作室 13.0.1
強大的PHP整合開發環境

Dreamweaver CS6
視覺化網頁開發工具

SublimeText3 Mac版
神級程式碼編輯軟體(SublimeText3)

C++中的眾數函數詳解在統計學中,眾數指的是一組資料中出現次數最多的數值。在C++語言中,我們可以透過寫一個眾數函數來找出任意一組資料中的眾數。眾數函數的實作可以採用多種不同的方法,以下將詳細介紹其中兩種常用的方法。第一種方法是使用哈希表來統計每個數字出現的次數。首先,我們需要定義一個哈希表,將每個數字作為鍵,出現次數作為值。然後,對於給定的資料集,我們遍

Windows作業系統是全球最受歡迎的作業系統之一,其新版本Win11備受矚目。在Win11系統中,管理員權限的取得是一個重要的操作,管理員權限可以讓使用者對系統進行更多的操作和設定。本文將詳細介紹在Win11系統中如何取得管理員權限,以及如何有效地管理權限。在Win11系統中,管理員權限分為本機管理員和網域管理員兩種。本機管理員是指具有對本機電腦的完全管理權限

OracleSQL中的除法運算詳解在OracleSQL中,除法運算是一種常見且重要的數學運算運算,用來計算兩個數相除的結果。除法在資料庫查詢中經常用到,因此了解OracleSQL中的除法運算及其用法是資料庫開發人員必備的技能之一。本文將詳細討論OracleSQL中除法運算的相關知識,並提供具體的程式碼範例供讀者參考。一、OracleSQL中的除法運算

C++中的取餘函數詳解在C++中,取餘運算子(%)用於計算兩個數相除的餘數。它是一種二元運算符,其運算元可以是任何整數型別(包括char、short、int、long等),也可以是浮點數型別(如float、double)。取餘運算子傳回的結果與被除數的符號相同。例如,對於整數的取餘運算,我們可以使用以下程式碼來實作:inta=10;intb=3;

Vue.nextTick函數用法詳解及在非同步更新中的應用在Vue開發中,經常會遇到需要進行非同步更新資料的情況,例如在修改DOM後需要立即更新資料或在資料更新後需要立即進行相關操作。而Vue提供的.nextTick函數就是為了解決這類問題而出現的。本文將會詳細介紹Vue.nextTick函數的用法,並結合程式碼範例來說明它在非同步更新中的應用。一、Vue.nex

PHP-FPM是一種常用的PHP流程管理器,用於提供更好的PHP效能和穩定性。然而,在高負載環境下,PHP-FPM的預設配置可能無法滿足需求,因此我們需要對其進行調優。本文將詳細介紹PHP-FPM的調優方法,並給予一些程式碼範例。一、增加進程數預設情況下,PHP-FPM只啟動少量的進程來處理請求。在高負載環境下,我們可以透過增加進程數來提高PHP-FPM的同時

PHP中的模運算子(%)是用來取得兩個數值相除的餘數的。在本文中,我們將詳細討論模運算子的作用及用法,並提供具體的程式碼範例來幫助讀者更好地理解。 1.模運算子的作用在數學中,當我們將一個整數除以另一個整數時,就會得到一個商和一個餘數。例如,當我們將10除以3時,商數為3,餘數為1。模運算子就是用來取得這個餘數的。 2.模運算子的用法在PHP中,使用%符號來表示模

Linux系統呼叫system()函數詳解系統呼叫是Linux作業系統中非常重要的一部分,它提供了一種與系統核心互動的方式。其中,system()函數是常用的系統呼叫函數之一。本文將詳細介紹system()函數的使用方法,並提供對應的程式碼範例。系統呼叫的基本概念系統呼叫是使用者程式與作業系統核心互動的一種方式。使用者程式透過呼叫系統呼叫函數來請求作業系統
