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Tcl

HTTP Request Boundary Property

Explains and demonstrates the HTTP request Boundary property. For multipart HTTP requests, Chilkat auto-generates a boundary string when the Boundary property is left unset (or empty). For example:
POST /something HTTP/1.1
Content-Type: multipart/form-data; boundary=------------090207000006060206010508
Host: domain
Content-Length: 378

--------------090207000006060206010508
Content-Disposition: form-data; name="fileA"; filename="fileA.txt"
Content-Type: text/plain

This is the contents of file A
--------------090207000006060206010508
Content-Disposition: form-data; name="fileB"; filename="fileB.txt"
Content-Type: text/plain

This is the contents of file B
--------------090207000006060206010508--

If the Boundary property is set, then Chilkat uses it. For example, if the Boundary property is set to "ABC123HELLOWORLD"
POST /something HTTP/1.1
Content-Type: multipart/form-data; boundary=ABC123HELLOWORLD
Host: domain
Content-Length: 318

--ABC123HELLOWORLD
Content-Disposition: form-data; name="fileA"; filename="fileA.txt"
Content-Type: text/plain

This is the contents of file A
--ABC123HELLOWORLD
Content-Disposition: form-data; name="fileB"; filename="fileB.txt"
Content-Type: text/plain

This is the contents of file B
--ABC123HELLOWORLD--

Chilkat Tcl Downloads

Tcl

load ./chilkat.dll

set req [new_CkHttpRequest]

CkHttpRequest_put_HttpVerb $req "POST"
CkHttpRequest_put_Path $req "/something"
CkHttpRequest_put_ContentType $req "multipart/form-data"

CkHttpRequest_AddStringForUpload $req "fileA" "fileA.txt" "This is the contents of file A" "utf-8"
CkHttpRequest_AddStringForUpload $req "fileB" "fileB.txt" "This is the contents of file B" "utf-8"

# When the Boundary property is empty (has not yet been set)
# Chilkat auto-generates a random boundary for the request.
# This should almost always be sufficient.
# For example, one can see the generated boundary here:
puts [CkHttpRequest_generateRequestText $req]

# If the Boundary property is set to a specific string, then the
# request will use it:
CkHttpRequest_put_Boundary $req "ABC123HELLOWORLD"
puts [CkHttpRequest_generateRequestText $req]

delete_CkHttpRequest $req