Question

我有一个Python / Tkinter程序，我试图增加一些数字，这些数字位于用于tk.Entry框的变量的末尾。

例如，self.output0，self.output1，self.output2等

（对不起，我的代码很长，所以我试着缩短它的例子。）

    self.entries = []
    self.output0 = tk.Entry(self, width=149, justify='center', bd='0', bg='#E0E0E0')
    self.output0.grid(column=0, row=6, columnspan=5, padx=1)

    self.output1 = tk.Entry(self, width=149, justify='center', bd='0', bg='#E0E0E0')
    self.output1.grid(column=0, row=7, columnspan=5, padx=1)

我使用另一个输入框抓取用户输入，例如＆self; first_first_entry＆＃39;并在用户输入上运行SQL查询。

例如：

class Adder(ttk.Frame):
    """The adders gui and functions."""
    def __init__(self, parent, *args, **kwargs):
        ttk.Frame.__init__(self, parent, *args, **kwargs)
        self.root = parent
        self.init_gui()

    def authenticate(self):
        return pypyodbc.connect('Driver={SQL Server};Server=MYSERVERNAME;Database=MYDATABASENAME;Trusted_Connection=yes;')

    def calculate(self):
        firstname = str(self.first_entry.get()) # converts user entry into variable
        lastname = str(self.last_entry.get())     
        license = str(self.lic_entry.get())

        try:
            connection = self.authenticate()
        except pypyodbc.Error as ex:
            sqlstate = ex.args[0]
            if sqlstate == '28000':
                self.output0.delete(0, END)
                self.output0.insert(0,"You do not have access.") 
        cursor = connection.cursor() 
        if (firstname and not lastname and not license):  # "You entered first name."
            SQLCommand = ("SELECT LASTNAME, FIRSTNAME, LICNUMBER "      
                "FROM MyTABLEName "   # table name
                "with (nolock)"
                "WHERE FIRSTNAME LIKE ?")
            Values = [firstname + '%']
        else:
            SQLCommand = ("SELECT LASTNAME, FIRSTNAME, LICNUMBER "      
                "FROM MyTABLEName "   # table name
                "(nolock)"
                "WHERE FIRSTNAME LIKE ? AND LASTNAME LIKE ? AND LICNUMBER LIKE ?")
            Values = [firstname + '%', lastname + '%', '%' + license + '%']
        cursor.execute(SQLCommand,Values)
        results = cursor.fetchmany(10)
        if results:
            self.output0.delete(0, END)  # clears entry
            self.output0.insert(0,results[0]) # enters results in entry
            self.output1.delete(0, END)  # clears entry
            self.output1.insert(0,results[1]) # enters results in entry
            self.output2.delete(0, END)  # clears entry
            self.output2.insert(0,results[2]) # enters results in entry
            self.output3.delete(0, END)  # clears entry
            self.output3.insert(0,results[3]) # enters results in entry
            self.output4.delete(0, END)  # clears entry
            self.output4.insert(0,results[4]) # enters results in entry
            connection.close()
        else:
            self.output0.delete(0, END)
            self.output0.insert(0,"There are no records for this input.")

以上将从数据库中输出5行。

我想缩短代码。我怎样才能采取以下内容并将其写下来，以便我不必重复

            self.output0.delete(0, END)  # clears entry
            self.output0.insert(0,results[0]) # enters results in entry
            self.output1.delete(0, END)  # clears entry
            self.output1.insert(0,results[1]) # enters results in entry
            2
            2
            3
            3
            ...etc

我想增加outputX和结果[x]

中的数字

以下是我一直在尝试的但它不起作用：

    cursor.execute(SQLCommand,Values)
    results = cursor.fetchmany(10)
    self.outputs =  [self.output0, self.output1, self.output2, self.output3, self.output4]
    for output in self.outputs:
        for i in range(0, 4):
            if results:
                output.delete(0, END)  # clears entry
                output.insert(0,results[i]) # enters results in entry
            else:
                self.output0.delete(0, END)
                self.output0.insert(0,"There are no records for this input.")

如何增加＆＃34;结果[x]＆＃34;中的数字？这样我从SQL查询中获得了不同的行？它在每一行上保持打印相同的行。

Answer 1

问题是您正在尝试索引光标。尝试先将其转换为列表，然后运行该功能。

results = list(cursor.fetchmany(10))

Answer 2

一个简单且不那么具有侵入性的解决方案是使用getattr：

def update_fields(self, prefix, values):
    for x, _ in enumerate(values):
        attr = getattr(self, prefix + str(x))
        attr.delete(0, END)
        attr.insert(0, values[x])

然后你就是：

results = cursor.fetchmany(10)
if results:
    self.update_fields('output', results)

请注意，getattr如果AttributeError没有名为self的声明字段<{p}}，则会引发outputX

您可以通过吞下异常来忽略未声明的字段：

def update_fields(self, prefix, values):
    for x, _ in enumerate(values):
        try:
            attr = getattr(self, prefix + str(x))
            attr.delete(0, END)
            attr.insert(0, values[x])
        except AttributeError:
            pass
            # You can also use continue

如何增加结果[0]中的数字？

2 个答案: