Tkinter格式化为两位小数

Question

这是针对Python 3.4版本的。 我在下面的代码中的工作原理； 但是我不能让我的DoubleVar（）公式带有2的十进制格式。 我将默认值设置为0.0到0.00，如何将其用作货币。

import tkinter
from tkinter import ttk

root = tkinter.Tk()
root.title("Change Counter")

ttk.Separator(root).grid(row=3, columnspan=5, sticky="ew")

dollarCoins = tkinter.IntVar()
halfDollars = tkinter.IntVar()
quarters = tkinter.IntVar()
dimes = tkinter.IntVar()
nickels = tkinter.IntVar()
pennies = tkinter.IntVar()

dollarCoinsTotal = tkinter.DoubleVar()
halfDollarTotal = tkinter.DoubleVar()
quartersTotal = tkinter.DoubleVar()
dimesTotal = tkinter.DoubleVar()
nickelsTotal = tkinter.DoubleVar()
penniesTotal = tkinter.DoubleVar()

titleLabel = tkinter.Label(root, text = "Change Counter")
titleLabel.grid(row=1, column=1, columnspan = 4)

def Totals():
    dollarCoinsTotal.set (float(dollarCoins.get()))
    halfDollarTotal.set(float(halfDollars.get()* 0.50))
    quartersTotal.set(float(quarters.get()* 0.25))
    dimesTotal.set(float(dimes.get()* 0.10))
    nickelsTotal.set(float(nickels.get()* 0.05))
    penniesTotal.set(float(pennies.get()* 0.01))

titleLabel = tkinter.Label(root, text = "Enter the number of each coin type and hit compute")
titleLabel.grid(row=2, column=1, columnspan =4)

dollarCoinsLabel = tkinter.Label(root, text = "Dollar Coins")
dollarCoinsLabel.grid(row=4, column=1, pady= 5)

dollarCoinsEntry = tkinter.Entry(root, textvariable = dollarCoins)
dollarCoinsEntry.grid(row=4, column=2, pady= 5, padx = 10)

halfDollarsLabel = tkinter.Label(root, text = "Half Dollars")
halfDollarsLabel.grid(row=5, column=1, pady= 5, padx = 10)

halfDollarsEntry = tkinter.Entry(root, textvariable = halfDollars)
halfDollarsEntry.grid(row=5, column=2, pady= 5)

quartersLabel = tkinter.Label(root, text = "Quarters")
quartersLabel.grid(row=6, column=1, pady= 5, padx = 10)

quartersEntry = tkinter.Entry(root, textvariable = quarters)
quartersEntry.grid(row=6, column=2, pady= 5)

dimesLabel = tkinter.Label(root, text = "Dimes")
dimesLabel.grid(row=7, column=1, pady= 5, padx = 10)

dimesEntry = tkinter.Entry(root, textvariable = dimes)
dimesEntry.grid(row=7, column=2, pady= 5)

nickelsLabel = tkinter.Label(root, text = "Nickels")
nickelsLabel.grid(row=8, column=1, pady= 5)

nickelsEntry = tkinter.Entry(root, textvariable = nickels)
nickelsEntry.grid(row=8, column=2, pady= 5, padx = 10)

penniesLabel = tkinter.Label(root, text = "Pennies")
penniesLabel.grid(row=9, column=1, pady= 5, padx = 10)

penniesEntry = tkinter.Entry(root, textvariable = pennies)
penniesEntry.grid(row=9, column=2, pady= 5)

dollarCoinsLabelText = tkinter.Label(root, text = "Dollar Coins Value: $")
dollarCoinsLabelText.grid(row=4, column=3, pady= 5, padx = 10)

dollarCoinsLabelValue = tkinter.Label(root, textvariable = dollarCoinsTotal)
dollarCoinsLabelValue.grid(row=4, column=4, pady= 5)

halfDollarLabelText = tkinter.Label(root, text = "Half Dollar Value: $")
halfDollarLabelText.grid(row=5, column=3, pady= 5, padx = 10)

halfDollarLabelValue = tkinter.Label(root, textvariable = halfDollarTotal)
halfDollarLabelValue.grid(row=5, column=4, pady= 5)

quartersLabelText = tkinter.Label(root, text = "Quarters Value: $")
quartersLabelText.grid(row=6, column=3, pady= 5, padx = 10)

quartersLabelValue = tkinter.Label(root, textvariable = quartersTotal)
quartersLabelValue.grid(row=6, column=4, pady= 5)

dimesLabelText = tkinter.Label(root, text = "Dimes Value: $")
dimesLabelText.grid(row=7, column=3, pady= 5, padx = 10)

dimesLabelValue = tkinter.Label(root, textvariable = dimesTotal)
dimesLabelValue.grid(row=7, column=4, pady= 5)

nickelsLabelText = tkinter.Label(root, text = "Nickels Value: $")
nickelsLabelText.grid(row=8, column=3, pady= 5, padx = 10)

nickelsLabelValue = tkinter.Label(root, textvariable = nickelsTotal)
nickelsLabelValue.grid(row=8, column=4, pady= 5)

penniesLabelText = tkinter.Label(root, text = "Pennies Value: $")
penniesLabelText.grid(row=9, column=3, pady= 5, padx = 10)

penniesLabelValue = tkinter.Label(root, textvariable = penniesTotal)
penniesLabelValue.grid(row=9, column=4, pady= 5)

calculateButton = tkinter.Button(root, text = "Compute", command = Totals)
calculateButton.grid(row=10, column=1)


root.mainloop()

Answer 1

这是我为自己想做的工作而想到的解决方案：

import tkinter
from tkinter import ttk

root = tkinter.Tk()
root.title("Change Counter")

#separator line
ttk.Separator(root).grid(row=2, columnspan=5, sticky="ew")

#Input Integers
dollarCoins = tkinter.IntVar()
halfDollars = tkinter.IntVar()
quarters = tkinter.IntVar()
dimes = tkinter.IntVar()
nickels = tkinter.IntVar()
pennies = tkinter.IntVar()

#Output Floats on right Side
dollarCoinsTotal = tkinter.DoubleVar()
dollarCoinsTotal.set('0.00')
halfDollarTotal = tkinter.DoubleVar()
halfDollarTotal.set('0.00')
quartersTotal = tkinter.DoubleVar()
quartersTotal.set('0.00')
dimesTotal = tkinter.DoubleVar()
dimesTotal.set('0.00')
nickelsTotal = tkinter.DoubleVar()
nickelsTotal.set('0.00')
penniesTotal = tkinter.DoubleVar()
penniesTotal.set('0.00')
allTotal = tkinter.DoubleVar()
allTotal.set('0.00')

#Title Document
titleLabel = tkinter.Label(root, text = "Change Counter", font = "-weight bold")
titleLabel.grid(row=1, column=1, columnspan = 4)

#Define Function for Button
#Format to be a floating point number of 2 decimals
def Totals():
    dollarCoinsTotal.set("{:.2f}".format(float(dollarCoins.get())))
    halfDollarTotal.set("{:.2f}".format(float(halfDollars.get()* 0.50)))
    quartersTotal.set("{:.2f}".format(float(quarters.get()* 0.25)))
    dimesTotal.set("{:.2f}".format(float(dimes.get()* 0.10)))
    nickelsTotal.set("{:.2f}".format(float(nickels.get()* 0.05)))
    penniesTotal.set("{:.2f}".format(float(pennies.get()* 0.01)))
    allTotal.set("{:.2f}".format(float(dollarCoinsTotal.get() + halfDollarTotal.get() + quartersTotal.get() + dimesTotal.get() + nickelsTotal.get() + penniesTotal.get())))

#Input statment for user
titleLabel = tkinter.Label(root, text = "Enter the number of each coin type and hit compute", font="-size 11")
titleLabel.grid(row=3, column=1, columnspan =4)

#Input Labels for Integers
dollarCoinsLabel = tkinter.Label(root, text = "Dollar Coins")
dollarCoinsLabel.grid(row=4, column=1, pady= 5)

dollarCoinsEntry = tkinter.Entry(root, textvariable = dollarCoins)
dollarCoinsEntry.grid(row=4, column=2, pady= 5, padx = 10)

halfDollarsLabel = tkinter.Label(root, text = "Half Dollars")
halfDollarsLabel.grid(row=5, column=1, pady= 5, padx = 10)

halfDollarsEntry = tkinter.Entry(root, textvariable = halfDollars)
halfDollarsEntry.grid(row=5, column=2, pady= 5)

quartersLabel = tkinter.Label(root, text = "Quarters")
quartersLabel.grid(row=6, column=1, pady= 5, padx = 10)

quartersEntry = tkinter.Entry(root, textvariable = quarters)
quartersEntry.grid(row=6, column=2, pady= 5)

dimesLabel = tkinter.Label(root, text = "Dimes")
dimesLabel.grid(row=7, column=1, pady= 5, padx = 10)

dimesEntry = tkinter.Entry(root, textvariable = dimes)
dimesEntry.grid(row=7, column=2, pady= 5)

nickelsLabel = tkinter.Label(root, text = "Nickels")
nickelsLabel.grid(row=8, column=1, pady= 5)

nickelsEntry = tkinter.Entry(root, textvariable = nickels)
nickelsEntry.grid(row=8, column=2, pady= 5, padx = 10)

penniesLabel = tkinter.Label(root, text = "Pennies")
penniesLabel.grid(row=9, column=1, pady= 5, padx = 10)

penniesEntry = tkinter.Entry(root, textvariable = pennies)
penniesEntry.grid(row=9, column=2, pady= 5)

#Output Labels for DoubleVars
dollarCoinsLabelText = tkinter.Label(root, text = "Dollar Coins Value: $")
dollarCoinsLabelText.grid(row=4, column=3, pady= 5, padx = 10)

dollarCoinsLabelValue = tkinter.Label(root, textvariable = dollarCoinsTotal)
dollarCoinsLabelValue.grid(row=4, column=4, pady= 5)

halfDollarLabelText = tkinter.Label(root, text = "Half Dollar Value: $")
halfDollarLabelText.grid(row=5, column=3, pady= 5, padx = 10)

halfDollarLabelValue = tkinter.Label(root, textvariable = halfDollarTotal)
halfDollarLabelValue.grid(row=5, column=4, pady= 5)

quartersLabelText = tkinter.Label(root, text = "Quarters Value: $")
quartersLabelText.grid(row=6, column=3, pady= 5, padx = 10)

quartersLabelValue = tkinter.Label(root, textvariable = quartersTotal)
quartersLabelValue.grid(row=6, column=4, pady= 5)

dimesLabelText = tkinter.Label(root, text = "Dimes Value: $")
dimesLabelText.grid(row=7, column=3, pady= 5, padx = 10)

dimesLabelValue = tkinter.Label(root, textvariable = dimesTotal)
dimesLabelValue.grid(row=7, column=4, pady= 5)

nickelsLabelText = tkinter.Label(root, text = "Nickels Value: $")
nickelsLabelText.grid(row=8, column=3, pady= 5, padx = 10)

nickelsLabelValue = tkinter.Label(root, textvariable = nickelsTotal)
nickelsLabelValue.grid(row=8, column=4, pady= 5)

penniesLabelText = tkinter.Label(root, text = "Pennies Value: $")
penniesLabelText.grid(row=9, column=3, pady= 5, padx = 10)

penniesLabelValue = tkinter.Label(root, textvariable = penniesTotal)
penniesLabelValue.grid(row=9, column=4, pady= 5)

allTotalLabelText = tkinter.Label(root, text = "Total Change Value: $", font="-weight bold -size 10", )
allTotalLabelText.grid(row=10, column=3, pady= 5, padx = 10)

allTotalLabelValue = tkinter.Label(root, textvariable = allTotal)
allTotalLabelValue.grid(row=10, column=4, pady= 5)

#Button to run calculations
calculateButton = tkinter.Button(root, text = "Compute", relief="raised", fg="red", font="-weight bold", command = Totals)
calculateButton.grid(row=10, column=1, columnspan =2, sticky = "EW", padx=5)


root.mainloop()

Answer 2

您可以使用.format() ，但是您的变量将被转换为字符串

dollars = 99.9                          #<== float value
strDollars = '{:.2f}'.format(dollars)
# strDollars = '99.90'                   <== string value

我希望这个对你有用！

Answer 3

不要将二进制浮点数用于货币计算，因为小数点值不会完全转换。 例如，float（.1）并不是真正的1.。 要么使用整数美分，将其格式化为美元格式的字符串，要么使用十进制十进制。 我做了前者。 下面唯一的更改是从DoubleVar到StringVar的切换，新的form（）函数和Totals的修订版。

import tkinter
from tkinter import ttk

root = tkinter.Tk()
root.title("Change Counter")

ttk.Separator(root).grid(row=3, columnspan=5, sticky="ew")

dollarCoins = tkinter.IntVar()
halfDollars = tkinter.IntVar()
quarters = tkinter.IntVar()
dimes = tkinter.IntVar()
nickels = tkinter.IntVar()
pennies = tkinter.IntVar()

dollarCoinsTotal = tkinter.StringVar()
halfDollarTotal = tkinter.StringVar()
quartersTotal = tkinter.StringVar()
dimesTotal = tkinter.StringVar()
nickelsTotal = tkinter.StringVar()
penniesTotal = tkinter.StringVar()

titleLabel = tkinter.Label(root, text = "Change Counter")
titleLabel.grid(row=1, column=1, columnspan = 4)

def form(pennies):
    return '{:d}.{:02d}'.format(*divmod(pennies, 100))

def Totals():
    dollarCoinsTotal.set (form(dollarCoins.get() * 100))
    halfDollarTotal.set(form(halfDollars.get() * 50))
    quartersTotal.set(form(quarters.get() * 25))
    dimesTotal.set(form(dimes.get() * 10))
    nickelsTotal.set(form(nickels.get() * 5))
    penniesTotal.set(form(pennies.get() * 1))

titleLabel = tkinter.Label(root, text = "Enter the number of each coin type and hit compute")
titleLabel.grid(row=2, column=1, columnspan =4)

dollarCoinsLabel = tkinter.Label(root, text = "Dollar Coins")
dollarCoinsLabel.grid(row=4, column=1, pady= 5)

dollarCoinsEntry = tkinter.Entry(root, textvariable = dollarCoins)
dollarCoinsEntry.grid(row=4, column=2, pady= 5, padx = 10)

halfDollarsLabel = tkinter.Label(root, text = "Half Dollars")
halfDollarsLabel.grid(row=5, column=1, pady= 5, padx = 10)

halfDollarsEntry = tkinter.Entry(root, textvariable = halfDollars)
halfDollarsEntry.grid(row=5, column=2, pady= 5)

quartersLabel = tkinter.Label(root, text = "Quarters")
quartersLabel.grid(row=6, column=1, pady= 5, padx = 10)

quartersEntry = tkinter.Entry(root, textvariable = quarters)
quartersEntry.grid(row=6, column=2, pady= 5)

dimesLabel = tkinter.Label(root, text = "Dimes")
dimesLabel.grid(row=7, column=1, pady= 5, padx = 10)

dimesEntry = tkinter.Entry(root, textvariable = dimes)
dimesEntry.grid(row=7, column=2, pady= 5)

nickelsLabel = tkinter.Label(root, text = "Nickels")
nickelsLabel.grid(row=8, column=1, pady= 5)

nickelsEntry = tkinter.Entry(root, textvariable = nickels)
nickelsEntry.grid(row=8, column=2, pady= 5, padx = 10)

penniesLabel = tkinter.Label(root, text = "Pennies")
penniesLabel.grid(row=9, column=1, pady= 5, padx = 10)

penniesEntry = tkinter.Entry(root, textvariable = pennies)
penniesEntry.grid(row=9, column=2, pady= 5)

dollarCoinsLabelText = tkinter.Label(root, text = "Dollar Coins Value: $")
dollarCoinsLabelText.grid(row=4, column=3, pady= 5, padx = 10)

dollarCoinsLabelValue = tkinter.Label(root, textvariable = dollarCoinsTotal)
dollarCoinsLabelValue.grid(row=4, column=4, pady= 5)

halfDollarLabelText = tkinter.Label(root, text = "Half Dollar Value: $")
halfDollarLabelText.grid(row=5, column=3, pady= 5, padx = 10)

halfDollarLabelValue = tkinter.Label(root, textvariable = halfDollarTotal)
halfDollarLabelValue.grid(row=5, column=4, pady= 5)

quartersLabelText = tkinter.Label(root, text = "Quarters Value: $")
quartersLabelText.grid(row=6, column=3, pady= 5, padx = 10)

quartersLabelValue = tkinter.Label(root, textvariable = quartersTotal)
quartersLabelValue.grid(row=6, column=4, pady= 5)

dimesLabelText = tkinter.Label(root, text = "Dimes Value: $")
dimesLabelText.grid(row=7, column=3, pady= 5, padx = 10)

dimesLabelValue = tkinter.Label(root, textvariable = dimesTotal)
dimesLabelValue.grid(row=7, column=4, pady= 5)

nickelsLabelText = tkinter.Label(root, text = "Nickels Value: $")
nickelsLabelText.grid(row=8, column=3, pady= 5, padx = 10)

nickelsLabelValue = tkinter.Label(root, textvariable = nickelsTotal)
nickelsLabelValue.grid(row=8, column=4, pady= 5)

penniesLabelText = tkinter.Label(root, text = "Pennies Value: $")
penniesLabelText.grid(row=9, column=3, pady= 5, padx = 10)

penniesLabelValue = tkinter.Label(root, textvariable = penniesTotal)
penniesLabelValue.grid(row=9, column=4, pady= 5)

calculateButton = tkinter.Button(root, text = "Compute", command = Totals)
calculateButton.grid(row=10, column=1)

root.mainloop()

过多的重复要求某种形式的重构，但我将其作为练习留给您。