(VB.NET) curl POST with JSON Input and JSON Output

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Note: This example requires Chilkat v11.5.0 or greater.

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Dim success As Boolean = False

' Run the following curl command

'  curl -X POST https://httpbin.org/post \
'       -H "Content-Type: application/json" \
'       -d '{
'             "title": "foo",
'             "body": "bar",
'             "userId": 1
'           }'

' The backslashes at the end of lines are not required.  Chilkat ignores them if present.
Dim sbTargetCurl As New Chilkat.StringBuilder
sbTargetCurl.AppendLn(" curl -X POST https://httpbin.org/post \")
sbTargetCurl.AppendLn("      -H ""Content-Type: application/json"" \")
sbTargetCurl.AppendLn("      -d '{")
sbTargetCurl.AppendLn("            ""title"": ""foo"",")
sbTargetCurl.AppendLn("            ""body"": ""bar"",")
sbTargetCurl.AppendLn("            ""userId"": 1")
sbTargetCurl.AppendLn("          }'")

Dim httpCurl As New Chilkat.HttpCurl

' Run the curl command.
success = httpCurl.DoYourThing(sbTargetCurl.GetAsString())
If (success = False) Then
    Debug.WriteLine(httpCurl.LastErrorText)
    Exit Sub
End If


Dim responseJson As New Chilkat.JsonObject
responseJson.EmitCompact = False

httpCurl.GetResponseJson(responseJson)

Dim statusCode As Integer = httpCurl.StatusCode
Debug.WriteLine("response status code: " & statusCode)

Debug.WriteLine(responseJson.Emit())

' Output:

' response status code: 200
' {
'   "args": {},
'   "data": "{\r\n            \"title\": \"foo\",\r\n            \"body\": \"bar\",\r\n            \"userId\": 1\r\n          }",
'   "files": {},
'   "form": {},
'   "headers": {
'     "Content-Length": "96",
'     "Content-Type": "application/json",
'     "Host": "httpbin.org",
'     "X-Amzn-Trace-Id": "Root=1-69e8db8b-459b3bdf7b7a3bc749184968"
'   },
'   "json": {
'     "body": "bar",
'     "title": "foo",
'     "userId": 1
'   },
'   "origin": "123.222.222.222",
'   "url": "https://httpbin.org/post"
' }

' ----------------------------------------------------------------------------------
' Another example:

' curl -X POST https://postman-echo.com/post \
'      -H "Content-Type: application/json" \
'      -d '{"foo":"bar"}'

Dim targetCurl As String = "curl -X POST https://postman-echo.com/post -H ""Content-Type: application/json"" -d '{""foo"":""bar""}'"

' Run the curl command.
success = httpCurl.DoYourThing(targetCurl)
If (success = False) Then
    Debug.WriteLine(httpCurl.LastErrorText)
    Exit Sub
End If


httpCurl.GetResponseJson(responseJson)

statusCode = httpCurl.StatusCode
Debug.WriteLine("response status code: " & statusCode)

Debug.WriteLine(responseJson.Emit())

' Output:

' response status code: 200
' {
'   "args": {},
'   "data": {
'     "foo": "bar"
'   },
'   "files": {},
'   "form": {},
'   "headers": {
'     "host": "postman-echo.com",
'     "content-length": "13",
'     "content-type": "application/json",
'     "x-forwarded-proto": "https",
'     "accept-encoding": "gzip, br"
'   },
'   "json": {
'     "foo": "bar"
'   },
'   "url": "https://postman-echo.com/post"
' }