Python使用字符串列表作为类数据成员。当字符串包含变量时，变量不会upd

Question

在类实例初始化之后，有没有办法更改类内列表中的变量(抱歉，听起来比实际情况复杂多了！）

我正在编写一个游戏，并将所有显示文本作为数组元素存储在“text”类的实例中。我编写了以下示例程序来测试我要做的事情：

#****************************************#
#INITIALIZE CLASS (to hold text component)
#****************************************#
class Text:
        def __init__(self, array, maxIndex):

            #list of text
            self.list = array

            #number of items in list
            self.max = maxIndex

#set global variable to 7
globalv = 7

#****************************************#
#INITIALIZE VARIABLE-ENHANCED TEXT
#necessary because variables inside class
#data member arrays seem to have a local
#scope, and can't be changed after they
#are initialized
#****************************************#
varLine = Text(["This line contains globalv, which holds: {}".format(globalv)], 0)

print varLine.list[varLine.max]
#prints 7

#CHANGE VALUE OF globalv:
print "Directly accessing globalv: {}".format(globalv)
#prints 7
print "\nUpdate value of globalv to 9"
globalv = 9
print "Directly accessing globalv: {}".format(globalv)
#prints 9

#Try to change and re-print variable
#doesn't work, despite the fact that "global" has changed outside of the class
print "\nfirst try:"

#call print function on globalv directly:
    print "Directly accessing globalv: {}".format(globalv)
    #prints 9

    #print it from the class:
    print "Printing from class:"
    print varLine.list[varLine.max])
    #prints 7

#Change variable by re-initializing class
print "\nsecond try:"
varLine = Text(["This line contains globalv, which holds: {}".format(globalv)], 0)

    #call print function on globalv directly:
    print "Directly accessing globalv: {}".format(globalv)
    #prints 9

    #print it from the class:
    print "Printing from class:"
    print varLine.list[varLine.max])
    #prints 9

Answer 1

代码工作正常。我不知道你在期待什么

将globalv转换为文本并将其存储在对象的文本中。当您稍后回来时，该文本字符串与您留下的文本字符串一样。您是否希望它会因为更改了globalv的值而发生神奇的变化？这有点像给自己拍照，换衣服，期望照片能换得和你的新衣服相配。变量不是这样工作的

也许你需要一个两步走的方法：

1. 创建一个属性来保存值，例如self.value
2. 编写一个显示对象属性的方法；在该方法中，访问self.value的current值，在生成的显示字符串中使用该值

有帮助吗