(Visual Basic 6.0) Viewing the Raw HTTP Request Generated from a curl Command

See more CURL Examples

This example demonstrates how to convert a curl command into the exact raw HTTP request that would be sent to the server—without actually sending it.

By calling ToRawRequest, the curl command is translated into its underlying HTTP representation, including the request line, headers, and body. This is especially useful for debugging, verifying request formatting, and understanding how a curl command maps to a real HTTP request.

In this example, a POST request with a JSON body is constructed using curl syntax. The code then converts it to the raw HTTP request format and prints the result. This allows you to inspect details such as the Content-Length, header formatting, and the exact payload being transmitted.

This technique is helpful when troubleshooting issues related to request composition, encoding, or server-side behavior.

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

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Dim success As Long
success = 0

' Build a curl command and convert it to the raw HTTP request that would be sent.
' This allows you to inspect the exact request (headers + body) without actually sending it.

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

Dim httpCurl As New ChilkatHttpCurl

' Convert the curl command into a raw HTTP request string.
' This is useful for debugging, as it shows exactly what would be sent to the server
' (request line, headers, and body) for the given curl command.
Dim sbRawRequest As New ChilkatStringBuilder
success = httpCurl.ToRawRequest(sbTargetCurl.GetAsString(),sbRawRequest)
If (success = 0) Then
    Debug.Print httpCurl.LastErrorText
    Exit Sub
End If

' Display the generated raw HTTP request.
Debug.Print sbRawRequest.GetAsString()

' Expected output:

' POST /post HTTP/1.1
' Host: httpbin.org
' Content-Type: application/json
' Content-Length: 96
' 
' {
'             "title": "foo",
'             "body": "bar",
'             "userId": 1
'           }