mechanize：为什么我的表单列表只包含 1 个元素？

Question

我是机械化新手，也不是最高级的 python 用户，但我想自动化一个我想给网页输入的任务。现在的问题是，“提交”按钮没有分配给它的控件名称。因此，我进行了一些研究，并找到了一种为相关表单设置值的方法。但要做到这一点，我必须访问我要为其赋值的特定表单。所以我的代码如下所示：

forms = [f for f in br.forms()]
print forms[0].controls[0].name

我只是想我可以通过写forms[x] 来访问该表单，然后是：

forms[x].set_value("VALUE", 
                       nr=5)

我得到的错误是：

    forms[54].set_value("VALUE",nr=100)
IndexError: list index out of range

这可能是一个有点愚蠢的问题，可能是因为我并不真正了解我正在使用的功能，但由于没有真正的纪录片，我非常感谢这里的一句帮助。

PS：我可以使用打印所有表格

for f in br.forms():
    print f

带输出：

 <CheckboxControl(lookup=[yes])>
  <TextControl(fld=NoName)>
  <TextControl(pixemail=)>
  <IgnoreControl(<None>=<None>)>
  <TextControl(ra=00 00 00.0)>
  <TextControl(dec=00 00 00.0)>
  <SelectControl(equinox=[*J2000.0, B1950.0])>
  <TextControl(offra=0.0)>
  <TextControl(offdec=0.0)>
  <TextControl(epoch=2000.0)>
  <SubmitControl(<None>= Retrieve Data ) (readonly)>
  <RadioControl(cextract=[*rect, circle])>
  <TextControl(rawid=10.0)>
  <TextControl(decwid=10.0)>
  <SelectControl(wunits=[Degrees, *Minutes, Seconds])>
  <TextControl(cirrad=10.0)>
  <SelectControl(cat=[UCAC 2, UCAC 3, NOMAD, *USNO B1.0, USNO A2.0, ACT])>
  <SelectControl(surims=[None, *All Surveys, POSS-I (103aO, 103aE), POSS-II (IIIaJ, IIIaF, IV-N), SOUTH, AAO-R, POSS-IO, POSS-IE, POSS-IIJ, POSS-IIF, POSS-IIN, SRC-J, SERC-EJ, ESO-R, SERC-ER])>
  <CheckboxControl(getcat=[*yes])>
  <CheckboxControl(getfin=[*yes])>
  <CheckboxControl(pixflg=[yes])>
  <CheckboxControl(colbits=[All, *cb_id, *cb_altid, *cb_ra, *cb_sigra, cb_mep, *cb_mura, cb_muprob, *cb_smura, cb_sfitra, *cb_fitpts, cb_err, *cb_flg, *cb_mag, cb_smag, *cb_mflg, *cb_fldid, *cb_sg, cb_xres, cb_pltidx, *cb_xi, *cb_dstctr, *cb_gall])>
  <RadioControl(skey=[*ra, dec, sigra, sigdec, mep, mura, mudec, muprob, smura, smudec, sfitra, sfitdec, fitpts, err, flg, mag, smag, mflg, fldid, sg, xres, yres, pltidx, clr, sigpos, mutot, sigmu, xi, eta, dstctr, gall, galb])>
  <SelectControl(slf=[*hh/dd mm ss, hh/dd:mm:ss, hh.hhh/dd.ddd, ddd.ddd/dd.ddd])>
  <TextControl(minnpts=0)>
  <TextControl(maxnpts=10)>
  <SelectControl(clr=[B1, R1, B2, *R2, I2, B, V, R, J, H, K])>
  <TextControl(bri=0)>
  <TextControl(fai=100)>
  <SelectControl(clr0m1A=[B1, R1, *B2, R2, I2, B, V, R, J, H, K])>
  <SelectControl(clr0m1B=[B1, R1, B2, *R2, I2, B, V, R, J, H, K])>
  <TextControl(bmrmin=-100)>
  <TextControl(bmrmax=100)>
  <TextControl(minposnerr=0.0)>
  <TextControl(maxposnerr=10000.0)>
  <TextControl(mumin=0.0)>
  <TextControl(mumax=10000.0)>
  <TextControl(minmuerr=0.0)>
  <TextControl(maxmuerr=10000.0)>
  <TextControl(minsep=0.0)>
  <HiddenControl(minmagerr=0.0) (readonly)>
  <HiddenControl(maxmagerr=1.0) (readonly)>
  <SelectControl(opstars=[Yes, *No])>
  <SelectControl(whorbl=[Light Stars/Dark Sky, *Dark Stars/Light Sky])>
  <SelectControl(pixgraph=[Progressive JPEG, *JPEG, GIF, PDF, Large JPEG (1 Survey Only), Large GIF (1 Survey Only), PS (1 Survey Only)])>
  <SelectControl(pixfits=[Yes, *No])>
  <SelectControl(ori=[NE - North Up, East Right, *NW - North Up, East Left, SE - North Down, East Right, SW - North Down, East Left, EN - East Up, North Right, ES - East Up, North Left, WN - East Down, North Right, WS - East Down, North Left])>
  <SelectControl(tck=[N and E marks, *Tick Marks, Grid Lines])>
  <SelectControl(starlbl=[Yes, *No])>
  <SelectControl(cmrk=[*None, 5.0 sec Box, 10.0 sec Box, 30.0 sec Box, 1.0 min Box, 2.0 min Box, 5.0 min Box, 10.0 min Box, 5.0 sec Circle, 10.0 sec Circle, 30.0 sec Circle, 1.0 min Circle, 2.0 min Circle, 5.0 min Circle, 10.0 min Circle])>
  <TextControl(aobj=none)>
  <SelectControl(pcl=[*P - Points, L - Points + Labels, C - Connected Points, A - Connected Points + Labels])>
  <TextareaControl(atbl=  )>
  <IgnoreControl(<None>=<None>)>
  <SubmitControl(<None>= Retrieve Data ) (readonly)>
  <SelectControl(gzf=[*Yes, No])>
  <SelectControl(cftype=[*ASCII, XML/VO])>>

我想上手的是<SubmitControl(<None>=Retrieve Data ) (readonly)>，从下往上数第三个。

Answer 1

试试这个：

import mechanize

br = mechanize.Browser()

# Insert the desired URL here
br.open('http://www.nofs.navy.mil/data/fchpix/cfch.html#fchmenu')
br.select_form(nr=0)

br["ra"] = "input 1"
br["dec"] = "input 2"
br["pixfits"] = ["Yes"]

br.find_control("pixflg").items[0].selected=True

response = br.submit()

Answer 2

我很确定有更好的方法来做到这一点 - 但我对机械化一点也不熟悉。您可以执行以下操作：

submit_values = filter(lambda x: 'SubmitControl' in str(x), br.forms())
if submit_values:
    print(submit_values[0])

如果有不止一个，显然你会得到不止一个。这可能是最奇怪的方式来完成你想要做的任何事情。此外，假设此表单是相当静态的，您可以将 Mechanize 的使用替换为 requests。然后它看起来像这样：

import requests

r = requests.post("http://form/action/url/goes/here", data={"lookup": "yes",
                                                            # all the other elements
                                                            })
print(r.status_code)
print(r.text)
# Do something else with r.text, e.g. scrape values with beautifulsoup or something

Answer 3

试试这个。您可以按控件类型搜索没有名称的控件。只是从记忆中去：

br.form.find_control(type='submit', nr=1)

我认为这是正确的语法。我会仔细检查并确定。