how to pass python variable to xpath expression?

[Ryan Chun Pui Keong]

Dear All,

I have a numeric variable called "index". How can pass it to xpath
expression?

For example, I would like to create an xpath expression like below.
But it doesn't work. Can anyone shed some light? Thanks.

hxs.select('div[@class="new"][$index]').extract()

BR,
Ryan

[Rolando Espinoza La Fuente]

On Sun, Dec 11, 2011 at 11:38 AM, Ryan Chun Pui Keong
<puik...@gmail.com> wrote:
> Dear All,
>
> I have a numeric variable called "index". How can pass it to xpath
> expression?

Is that "index" variable a python variable?

If so, you can use usual python's string interpolation:

xpath = "//foo/bar[%s]" % index

xpath = "//foo/bar[{0}]".format(index)
xpath = "//foo/bar[{index}]".format(index=index)

results = hxs.select(xpath)

The .format() statements are supported in python 2.6+.

Regards,

~Rolando

> For example, I would like to create an xpath expression like below.
> But it doesn't work. Can anyone shed some light? Thanks.
>
> hxs.select('div[@class="new"][$index]').extract()
>
> BR,
> Ryan
>

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[Tomas Neme]

you can also do this:

xpath = "//foo/bar[%d]"

for index in range(some_number):
    results = hxs.select(xpath % index)

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[Ryan Chun Pui Keong]

Hi Guys, thanks so much for your help!