Excel VBAのWinHTTPライブラリ：インターネット通信を自動化する強力なツール

Sub GetRequestExample()
    ' WinHTTPライブラリの参照設定が必要
    ' 参照設定: Microsoft WinHTTP Services, version 5.1

    Dim httpRequest As WinHttp.WinHttpRequest
    Dim url As String
    Dim response As String

    url = "https://api.exchangerate-api.com/v4/latest/USD"

    ' WinHttpRequestオブジェクトの作成
    Set httpRequest = New WinHttp.WinHttpRequest

    ' HTTP GETリクエストの設定
    httpRequest.Open "GET", url, False
    httpRequest.send

    ' サーバーの応答を取得
    response = httpRequest.ResponseText

    ' 応答をメッセージボックスに表示
    MsgBox response, vbInformation, "Webサービスからの応答"

    ' Excelシートにデータを表示
    Dim ws As Worksheet
    Set ws = ThisWorkbook.Sheets(1)
    ws.Cells(1, 1).Value = response

    ' リソースの解放
    Set httpRequest = Nothing
End Sub

Sub PostRequestExample()
    ' WinHTTPライブラリの参照設定が必要
    ' 参照設定: Microsoft WinHTTP Services, version 5.1

    Dim httpRequest As WinHttp.WinHttpRequest
    Dim url As String
    Dim postData As String
    Dim response As String

    url = "https://jsonplaceholder.typicode.com/posts"
    postData = "{""title"":""foo"",""body"":""bar"",""userId"":1}"

    ' WinHttpRequestオブジェクトの作成
    Set httpRequest = New WinHttp.WinHttpRequest

    ' HTTP POSTリクエストの設定
    httpRequest.Open "POST", url, False
    httpRequest.setRequestHeader "Content-Type", "application/json"
    httpRequest.send postData

    ' サーバーの応答を取得
    response = httpRequest.ResponseText

    ' 応答をメッセージボックスに表示
    MsgBox response, vbInformation, "サーバーからの応答"

    ' Excelシートにデータを表示
    Dim ws As Worksheet
    Set ws = ThisWorkbook.Sheets(1)
    ws.Cells(1, 1).Value = response

    ' リソースの解放
    Set httpRequest = Nothing
End Sub

Sub GetRequestWithErrorHandling()
    ' WinHTTPライブラリの参照設定が必要
    ' 参照設定: Microsoft WinHTTP Services, version 5.1

    Dim httpRequest As WinHttp.WinHttpRequest
    Dim url As String
    Dim response As String

    On Error GoTo ErrorHandler

    url = "https://api.exchangerate-api.com/v4/latest/USD"

    ' WinHttpRequestオブジェクトの作成
    Set httpRequest = New WinHttp.WinHttpRequest

    ' HTTP GETリクエストの設定
    httpRequest.Open "GET", url, False
    httpRequest.send

    ' サーバーの応答を取得
    response = httpRequest.ResponseText

    ' 応答をメッセージボックスに表示
    MsgBox response, vbInformation, "Webサービスからの応答"

    ' Excelシートにデータを表示
    Dim ws As Worksheet
    Set ws = ThisWorkbook.Sheets(1)
    ws.Cells(1, 1).Value = response

    ' リソースの解放
    Set httpRequest = Nothing
    Exit Sub

ErrorHandler:
    MsgBox "エラーが発生しました: " & Err.Description, vbCritical, "エラー"
    Set httpRequest = Nothing
End Sub

Sub GetRequestWithAuthentication()
    ' WinHTTPライブラリの参照設定が必要
    ' 参照設定: Microsoft WinHTTP Services, version 5.1

    Dim httpRequest As WinHttp.WinHttpRequest
    Dim url As String
    Dim apiKey As String
    Dim response As String

    url = "https://api.example.com/data"
    apiKey = "YOUR_API_KEY"

    ' WinHttpRequestオブジェクトの作成
    Set httpRequest = New WinHttp.WinHttpRequest

    ' HTTP GETリクエストの設定
    httpRequest.Open "GET", url, False
    httpRequest.setRequestHeader "Authorization", "Bearer " & apiKey
    httpRequest.send

    ' サーバーの応答を取得
    response = httpRequest.ResponseText

    ' 応答をメッセージボックスに表示
    MsgBox response, vbInformation, "Webサービスからの応答"

    ' Excelシートにデータを表示
    Dim ws As Worksheet
    Set ws = ThisWorkbook.Sheets(1)
    ws.Cells(1, 1).Value = response

    ' リソースの解放
    Set httpRequest = Nothing
End Sub