Excel Web Query Submit Issues

Question

I'm trying to get data (dollar exchange rate) from http://www4.bcb.gov.br/pec/taxas/port/ptaxnpesq.asp?id=txcotacao into a excel spreadsheet.

I've tried to paste as refreshable web query, however, the page always open one step earlier with a form, which has already default inputs (that works for me) and then the query copies stuff from this page.

I also tried to write a code to submit the form, but I didn't get it right. I tried the .submit, .Click, .FireEvent and many other things I found on internet.

I tried to refer to the button by its name, class, tag, ...

false

I also tried to trigger the form directly or bypass it, but didn't work

var invoice = Invoice.Get(apiContext, "INV2-XXXX-XXXX-XXXX");
string transactionId = invoice.payments.First().transaction_id;

Can anyone help me with this piece of code?

Answer 1

您可以使用bcb.gov.br Open Data Portal。

使用Exchange rates – daily bulletins的转化率发送JSON回复请求。

通过收到的回复，以及其他方法，您可以：

1. 使用JSON Converter并将响应转换为JSON对象并使用它;
2. 将响应解析为带有正则表达式的字符串以获取值

查看site上

>今日结果的结果

<强>输入：



<强>输出：



结果：

您可以看到1美元= 3,7048巴西雷亚尔

①使用JSON对象：

要发出请求的示例字符串：

"https://olinda.bcb.gov.br/olinda/service/PTAX/version/v1/odata/ExchangeRatePeriod(moeda=@moeda,dataInicial=@dataInicial,dataFinalCotacao=@dataFinalCotacao)?%40moeda=%27" & TARGET_CURRENCY & "%27&%40dataInicial=%27" & START_DATE & "%27&%40dataFinalCotacao=%27" & END_DATE & "%27&%24format=json"

我在字符串中包含开始日期，结束日期和货币，并将响应格式指定为JSON。我选择的日期与上图中显示的网站视图相匹配。

JSON响应如下：



我将响应读入字符串变量，然后使用JsonConverter.ParseJson(strJSON)转换为存储在json变量中的JSON对象。快速检查结构：



开始＆＃34; {＆＃34;告诉我json是一本字典。



我还可以看到json("value")是一个字典集合，我感兴趣的值3,7048 - 请记住上面的网站图片，存储为"cotacaoCompra"。< / p>

因此我可以使用以下脚本来访问该值。 JSON响应实际上在该日期的5个不同时间给出了费率。这些都打印出来了。我们可以看到Fechamento（结案）公告3,7048的比赛。

<强>代码：

Option Explicit
Public Sub GetInfo()
    Dim strURL As String, strJSON As String, item As Variant, http As Object, json As Object
    Const TARGET_CURRENCY As String = "USD"
    Const START_DATE As String = "06-13-2018"
    Const END_DATE As String = "06-13-2018"

    strURL = "https://olinda.bcb.gov.br/olinda/service/PTAX/version/v1/odata/ExchangeRatePeriod(moeda=@moeda,dataInicial=@dataInicial,dataFinalCotacao=@dataFinalCotacao)?%40moeda=%27" & TARGET_CURRENCY & "%27&%40dataInicial=%27" & START_DATE & "%27&%40dataFinalCotacao=%27" & END_DATE & "%27&%24format=json"

    Set http = CreateObject("MSXML2.XMLHTTP")
    http.Open "GET", strURL, False
    http.send
    strJSON = http.responseText
    Set json = JsonConverter.ParseJson(strJSON)

    For Each item In json("value")
        Debug.Print "rate " & item("cotacaoCompra") & " at " & item("dataHoraCotacao")
    Next item
End Sub

脚本输出：



备注：

需要添加JSONConverter bas和VBE＆gt;工具＆gt;参考文献＆gt; Microsoft Scripting RunTime）

②使用正则表达式解析responseText以获取费率：

我将使用的正则表达式是

"cotacaoCompra":\d{1,}.\d{1,}

这会查找文字字符串"cotacaoCompra":，然后是一个或多个数字，然后是＆＃34;。＆＃34;，然后是一个或多个数字。



然后我必须通过直接替换删除字符串"cotacaoCompra":。理想情况下，我只需用"(?<=""cotacaoCompra"":)\d{1,}.\d{1,}"提取数字;基本上，之后说，但不包括"cotacaoCompra":。但这似乎并不受支持。

考虑到这一点，使用正则表达式获取费率的脚本：

<强>代码：

Public Sub GetInfo2()

    Dim strURL As String, strJSON As String, item As Variant, http As Object, json As Object
    Const TARGET_CURRENCY As String = "USD"
    Const START_DATE As String = "06-13-2018"
    Const END_DATE As String = "06-13-2018"

    strURL = "https://olinda.bcb.gov.br/olinda/service/PTAX/version/v1/odata/ExchangeRatePeriod(moeda=@moeda,dataInicial=@dataInicial,dataFinalCotacao=@dataFinalCotacao)?%40moeda=%27" & TARGET_CURRENCY & "%27&%40dataInicial=%27" & START_DATE & "%27&%40dataFinalCotacao=%27" & END_DATE & "%27&%24format=json"

    Set http = CreateObject("MSXML2.XMLHTTP")
    http.Open "GET", strURL, False
    http.send
    strJSON = http.responseText
    Dim Matches As Object
    With CreateObject("VBScript.RegExp")
        .Global = True
        .MultiLine = True
        .IgnoreCase = False
        .Pattern = """cotacaoCompra"":\d{1,}.\d{1,}"  'The pattern I really wanted, "(?<=""cotacaoCompra"":)\d{1,}.\d{1,}", doesn't appear to be supported

        If Not .test(strJSON) Then Exit Sub
        Set Matches = .Execute(strJSON)

        Dim match As Object
        For Each match In Matches
            Debug.Print Replace(match, """cotacaoCompra"":", vbNullString)
        Next
    End With
End Sub