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C#

PayPal Send Invoice

See more PayPal Examples

Sends a PayPal invoice to a customer.

See also Send Invoice

Chilkat C# Downloads

C#
bool success = false;

// Note: Requires Chilkat v9.5.0.64 or greater.

// This requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// Load our previously obtained access token. (see PayPal OAuth2 Access Token)
Chilkat.JsonObject jsonToken = new Chilkat.JsonObject();
jsonToken.LoadFile("qa_data/tokens/paypal.json");

// Build the Authorization request header field value.
Chilkat.StringBuilder sbAuth = new Chilkat.StringBuilder();
// token_type should be "Bearer"
sbAuth.Append(jsonToken.StringOf("token_type"));
sbAuth.Append(" ");
sbAuth.Append(jsonToken.StringOf("access_token"));

// Make the initial connection.
// A single REST object, once connected, can be used for many PayPal REST API calls.
// The auto-reconnect indicates that if the already-established HTTPS connection is closed,
// then it will be automatically re-established as needed.
Chilkat.Rest rest = new Chilkat.Rest();
bool bAutoReconnect = true;
success = rest.Connect("api.sandbox.paypal.com",443,true,bAutoReconnect);
if (success != true) {
    Debug.WriteLine(rest.LastErrorText);
    return;
}

// ----------------------------------------------------------------------------------------------
// The code above this comment could be placed inside a function/subroutine within the application
// because the connection does not need to be made for every request.  Once the connection is made
// the app may send many requests..
// ----------------------------------------------------------------------------------------------

// Build a path using a draft invoice ID.
Chilkat.StringBuilder sbPath = new Chilkat.StringBuilder();
sbPath.Append("/v1/invoicing/invoices/invoice_id/send");
int numReplacements = sbPath.Replace("invoice_id","INV2-QCHR-QHSD-M2VU-AVXC");

rest.AddHeader("Authorization",sbAuth.GetAsString());
rest.AddQueryParam("notify_merchant","true");

string responseBody = rest.FullRequestFormUrlEncoded("POST",sbPath.GetAsString());
if (rest.LastMethodSuccess != true) {
    Debug.WriteLine(rest.LastErrorText);
    return;
}

Debug.WriteLine("Response Status Code = " + Convert.ToString(rest.ResponseStatusCode));

// Did we get a 202 accepted response?
if (rest.ResponseStatusCode != 202) {
    Debug.WriteLine(responseBody);
    Debug.WriteLine("Failed.");
    return;
}

// If the 202 response is received, the response body would be empty...
Debug.WriteLine("Success.");