我正在尝试通过PowerShell读取XML文件。
示例XML：
import tkinter as tk
data = {
"easy": [
[8,0,0,0,4,0,6,7,0],
[0,3,0,6,7,0,5,0,8],
[0,7,2,0,0,0,0,3,4],
[1,0,3,7,0,4,8,0,5],
[0,6,5,0,1,8,4,9,0],
[0,4,8,0,5,6,0,2,0],
[5,9,0,4,2,0,0,0,0],
[2,0,7,0,3,0,1,0,6],
[3,0,4,0,6,0,2,0,9],
],
"hard": [
[0,8,0,3,0,5,0,1,0],
[1,0,0,0,0,0,0,0,0],
[0,0,3,2,0,0,6,0,0],
[0,0,7,0,0,0,0,9,8],
[8,0,2,0,5,0,4,0,3],
[4,1,0,0,0,0,2,0,0],
[0,0,4,0,0,8,9,0,0],
[0,0,0,0,0,0,0,0,1],
[0,9,0,7,0,6,0,8,0],
],
}
solved = {
"easy": [
[8,5,1,9,4,3,6,7,2],
[4,3,9,6,7,2,5,1,8],
[6,7,2,1,8,5,9,3,4],
[1,2,3,7,9,4,8,6,5],
[7,6,5,2,1,8,4,9,3],
[9,4,8,3,5,6,7,2,1],
[5,9,6,4,2,1,3,8,7],
[2,8,7,5,3,9,1,4,6],
[3,1,4,8,6,7,2,5,9],
],
"hard": [
[2,8,6,3,4,5,7,1,9],
[1,4,5,6,9,7,8,3,2],
[9,7,3,2,8,1,6,4,5],
[3,5,7,4,6,2,1,9,8],
[8,6,2,1,5,9,4,7,3],
[4,1,9,8,7,3,2,5,6],
[6,3,4,5,1,8,9,2,7],
[7,2,8,9,3,4,5,6,1],
[5,9,1,7,2,6,3,8,4],
],
}
def left_click(widget):
''' process button click '''
# get next value (modulo 10)
widget.value = (widget.value+1) % 10
# if zero then put empty string
if widget.value == 0:
widget['text'] = ''
else:
widget['text'] = widget.value
def create_empty_board(master):
''' create board with empty buttons '''
# create black lines
master['bg'] = '#444'
master.columnconfigure(3, minsize=3)
master.columnconfigure(7, minsize=3)
master.rowconfigure(3, minsize=3)
master.rowconfigure(7, minsize=3)
all_buttons = []
for r in range(11):
# skip rows to create black lines
if r in (3, 7):
continue
row_buttons = []
for c in range(11):
# skip columns to create black lines
if c in (3, 7):
continue
b = tk.Button(master, text='-')
b.grid(row=r, column=c, sticky='we')
row_buttons.append(b)
all_buttons.append(row_buttons)
return all_buttons
def reset_board(all_buttons, local_data):
''' reset buttons on board without creating new buttons '''
for row_buttons, row_sudoku in zip(all_buttons, local_data):
for b, v in zip(row_buttons,row_sudoku):
# create unstandard variable to keep current value on button
b.value = v
if v == 0:
b['text'] = ' '
b['command'] = lambda but=b:left_click(but)
#b['fg'] = 'black'
b['bg'] = '#ddd'
b['state'] = 'normal'
b['disabledforeground'] = 'black'
else:
b['text'] = v
b['command'] = None
#b['fg'] = 'blue'
b['bg'] = '#cce'
b['state'] = 'disabled'
b['disabledforeground'] = 'blue'
def check_buttons():
''' compare buttons with `solved` '''
local_data = solved[difficalty]
for r, (row_buttons, row_sudoku) in enumerate(zip(all_buttons, local_data), 1):
row_ok = True
for c, (b, v) in enumerate(zip(row_buttons,row_sudoku), 1):
if b.value != v:
print('wrong row: {}, col: {}, button: {}, expected: {}'.format(r, c, b.value, v))
row_ok = False
if row_ok:
print('OK row:', r)
def change_difficalty(level):
''' change difficalty and reset board '''
global difficalty
difficalty = level
reset_board(all_buttons, data[difficalty])
# --- main ---
difficalty = "easy"
root = tk.Tk()
board = tk.Frame(root)
board.pack()
all_buttons = create_empty_board(board)
reset_board(all_buttons, data[difficalty])
b = tk.Button(root, text="Easy", command=lambda:change_difficalty("easy"))
b.pack()
b = tk.Button(root, text="Hard", command=lambda:change_difficalty("hard"))
b.pack()
b = tk.Button(root, text="Check board", command=check_buttons)
b.pack()
root.mainloop()
示例代码：
<branches>
<branch>refs/heads/master</branch>
<branch Version="6.0.7">develop/4.0</branch>
</branches>
问题是属性$xml = [xml](Get-Content $xmlfile)
foreach ($branch in $xml.branches.branch) {
$version = $branch.Version
}
是可选的，PowerShell将第一次出现的Version解释为字符串。第二次出现工作正常。我需要它们都是XmlElement。我已经尝试将branch转换为XmlElements数组而没有成功。
如何转换为XmlElement？
答案 0 :(得分：1)
SelectSingleNode()使用XPath expression而非点访问：
$version = $xml.SelectSingleNode('//branches/branch/@Version').'#text'