Classic ASP Requires Chilkat v11.7.0+
Box: Upload a File from BinData

Run the reusable setup once per HttpCurl object, then select names and execute the operation. The setup is repeated here only to make this published example independently runnable. Resolve documents by name using HttpCurl, then upload a small local PDF from BinData with Rest. The transfer is explicit after dependency resolution; no ID is entered by the caller.
See the Box API guide for setup and the complete workflow.
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<%
success = 0

'  Requires Chilkat 11.7.0 or later and a previously unlocked Chilkat bundle.
'  See Global Unlock Sample.
'  Guide: Box API Guide.

success = 0

'  BEGIN ONE-TIME SETUP
'  This block is repeated so each published example can run on its own.
'  In an application, run the setup example once and pass the SAME curl object
'  to operation code below. Do not recreate it for every operation.
'  See Reusable Box HttpCurl Setup.
set curl = Server.CreateObject("Chilkat.HttpCurl")
curl.SetVar "access_token","BOX_ACCESS_TOKEN"
curl.SetVar "parent_name","/"
'  Box's fixed root ID is an implementation detail; callers supply names.
curl.SetVar "parent_id","0"
set setupCommand = Server.CreateObject("Chilkat.StringBuilder")

'  Register findParent; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("findParent",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register findFolder; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/folders/{{parent_id}}/items?limit=1000&fields=id,type,name"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("findFolder",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register findFile; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/folders/{{folder_id}}/items?limit=1000&fields=id,type,name"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("findFile",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register findDestination; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("findDestination",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register getFileDetails; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/files/{{file_id}}?fields=id,sha1,file_version"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("getFileDetails",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register getEnterprise; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/users/me?fields=enterprise"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("getEnterprise",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register output rules once. Chilkat 11.7.0 evaluates {{name}} variables
'  when extracting each output, using the current value at that time.
success = curl.AddOutput2("findParent","entries","name","{{parent_name}}",1,"id","parent_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput2("findFolder","entries","name","{{folder_name}}",1,"id","folder_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput2("findFile","entries","name","{{file_name}}",1,"id","file_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput2("findDestination","entries","name","{{destination_name}}",1,"id","destination_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput("getFileDetails","file_version.id","file_version_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput("getFileDetails","sha1","file_sha1")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput("getEnterprise","enterprise.id","enterprise_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  END ONE-TIME SETUP
'  The name lookups below assume each listing fits in one page (1000 items).
'  Parent and destination names select root children; folder_name selects a child
'  of parent_name. "/" selects the root parent. These are not arbitrary paths.

'  BEGIN OPERATION -- keep the configured object when reusing it.
'  Inputs are names. Retain cached IDs when the selected names have not changed.
parentName = "/"
folderName = "documents"
If ((curl.GetVar("parent_name") <> parentName) Or ((parentName = "/") And (curl.VarDefined("parent_id") = 0))) Then
    curl.SetVar "parent_name",parentName
    curl.ClearVar "parent_id"
    curl.ClearVar "folder_id"
    curl.ClearVar "file_id"
    curl.ClearVar "file_version_id"
    curl.ClearVar "file_sha1"
    If (parentName = "/") Then
        curl.SetVar "parent_id","0"
    End If

End If

If (curl.GetVar("folder_name") <> folderName) Then
    curl.SetVar "folder_name",folderName
    curl.ClearVar "folder_id"
    curl.ClearVar "file_id"
    curl.ClearVar "file_version_id"
    curl.ClearVar "file_sha1"
End If

'  Resolve the named destination first. HttpCurl does not expand variables
'  inside multipart -F attributes in the tested build, so this upload is two phases.
curl.ClearTargetOutput "*"
set authorizedCommand1 = Server.CreateObject("Chilkat.StringBuilder")
success = authorizedCommand1.SetString("curl -X GET ""https://api.box.com/2.0/folders/{{folder_id}}?fields=id"" -H ""Authorization: Bearer {{access_token}}""")
headerReplacement1 = authorizedCommand1.Replace("{{access_token}}",curl.GetVar("access_token"))
success = curl.DoYourThing(authorizedCommand1.GetAsString())
If ((success <> 1) Or (curl.StatusCode <> 200)) Then
    Response.Write "<pre>" & Server.HTMLEncode( "Box request failed. HTTP status: " & curl.StatusCode) & "</pre>"
    Response.Write "<pre>" & Server.HTMLEncode( "Failure reason: " & curl.FailReason) & "</pre>"
    Response.Write "<pre>" & Server.HTMLEncode( curl.ResponseBodyStr) & "</pre>"
    Response.End
End If

set data = Server.CreateObject("Chilkat.BinData")
success = data.LoadFile("qa_data/pdf/invoice.pdf")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( data.LastErrorText) & "</pre>"
    Response.End
End If

set rest = Server.CreateObject("Chilkat.Rest")
set oauth2 = Server.CreateObject("Chilkat.OAuth2")
oauth2.AccessToken = curl.GetVar("access_token")
success = rest.SetAuthOAuth2(oauth2)
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rest.LastErrorText) & "</pre>"
    Response.End
End If

success = rest.Connect("upload.box.com",443,1,1)
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rest.LastErrorText) & "</pre>"
    Response.End
End If

set attributes = Server.CreateObject("Chilkat.JsonObject")
success = attributes.UpdateString("name","invoice.pdf")
success = attributes.UpdateString("parent.id",curl.GetVar("folder_id"))
success = rest.AddHeader("Content-Type","multipart/form-data")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rest.LastErrorText) & "</pre>"
    Response.End
End If

rest.PartSelector = "1"
success = rest.AddHeader("Content-Disposition","form-data; name=""attributes""")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rest.LastErrorText) & "</pre>"
    Response.End
End If

success = rest.SetMultipartBodyString(attributes.Emit())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rest.LastErrorText) & "</pre>"
    Response.End
End If

rest.PartSelector = "2"
success = rest.AddHeader("Content-Disposition","form-data; name=""file""; filename=""invoice.pdf""")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rest.LastErrorText) & "</pre>"
    Response.End
End If

success = rest.AddHeader("Content-Type","application/pdf")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rest.LastErrorText) & "</pre>"
    Response.End
End If

success = rest.SetMultipartBodyBd(data)
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rest.LastErrorText) & "</pre>"
    Response.End
End If

rest.PartSelector = "0"
responseBody = rest.FullRequestMultipart("POST","/api/2.0/files/content")
If (rest.LastMethodSuccess <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rest.LastErrorText) & "</pre>"
    Response.End
End If

If (rest.ResponseStatusCode <> 201) Then
    Response.Write "<pre>" & Server.HTMLEncode( "Upload failed: " & rest.ResponseStatusCode) & "</pre>"
    Response.Write "<pre>" & Server.HTMLEncode( responseBody) & "</pre>"
    Response.End
End If

set result = Server.CreateObject("Chilkat.JsonObject")
success = result.Load(responseBody)
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( result.LastErrorText) & "</pre>"
    Response.End
End If

Response.Write "<pre>" & Server.HTMLEncode( "Uploaded file ID: " & result.StringOf("entries[0].id")) & "</pre>"
curl.SetVar "file_name","invoice.pdf"
curl.SetVar "file_id",result.StringOf("entries[0].id")
curl.ClearVar "file_version_id"
curl.ClearVar "file_sha1"

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