字符串替换-不支持的格式字符'}'

Question

I'm trying to do some string substitution for html/javascript templating, however when the page string variable has a curly brace in the code, I get the error of "ValueError: unsupported format character '}' (0x7d)". 我正在尝试为html / javascript模板做一些字符串替换，但是，当页面字符串变量在代码中花括号时，出现错误“ ValueError：不支持的格式字符'}'（0x7d）”。 If I don't have any string substitution everything works fine. 如果我没有任何字符串替换，则一切正常。 Thanks for reading! 谢谢阅读！

import webapp2
page = """
<html>
    <style type="text/css">
      html { height: 100% }
      body { height: 100%; margin: 0; padding: 0 }
      #map_canvas { height: 100% }
    </style>
    %(say)s
</html>
    """

class MainHandler(webapp2.RequestHandler):
    def write_form(self, say):
        self.response.out.write(page % { "say": say })

    def get(self):
        self.write_form("hello")

app = webapp2.WSGIApplication([('/', MainHandler)],
                              debug=True)

Answer 1

Your 'template' contains the string % } (right after the 100 there), and python is interpreting that as a formatting instruction. 您的“模板”包含字符串% } （紧随其后的100 ），而python会将其解释为格式指令。

Double the % percent characters to %% and it'll work. 将%百分比字符加倍至%% ，它将起作用。

>>> page = """
... <html>
...     <style type="text/css">
...       html { height: 100%% }
...       body { height: 100%%; margin: 0; padding: 0 }
...       #map_canvas { height: 100%% }
...     </style>
...     %(say)s
... </html>
...     """
>>> page % dict(say='foo')
'\n<html>\n    <style type="text/css">\n      html { height: 100% }\n      body { height: 100%; margin: 0; padding: 0 }\n      #map_canvas { height: 100% }\n    </style>\n    foo\n</html>\n    '

Alternatively, use the newer .format() method for a format less prone to such problems, although in this specific case that'll get hung up on the { height: 100% } curly braces pairs, so your mileage may very well vary; 或者，使用较新的.format()方法处理不太容易出现此类问题的格式，尽管在这种特定情况下，该电话将挂在{ height: 100% }花括号对上，因此您的行距可能会非常不同； you'd have to double those instead (so {{ height: 100% }} ). 您必须将其翻倍（因此{{ height: 100% }} ）。

字符串替换-不支持的格式字符'}'

问题描述

1 个解决方案

解决方案1
4 已采纳 2012-09-07 09:04:28

字符串替换-不支持的格式字符&#39;}&#39;

问题描述

1 个解决方案

解决方案1 4 已采纳 2012-09-07 09:04:28

字符串替换-不支持的格式字符'}'

解决方案1
4 已采纳 2012-09-07 09:04:28