使用的WSDL，添加为服务参考而非网络参考。
//The client object
cb.Clearbooks_Service_ApiPortClient client = new cb.Clearbooks_Service_ApiPortClient();
//The apiKey object
cb.authenticate auth = new cb.authenticate();
auth.apiKey = "YOUR_API_KEY";
private void button1_Click(object sender, EventArgs e)
{
//The client object
cb.Clearbooks_Service_ApiPortClient client = new cb.Clearbooks_Service_ApiPortClient();
//The apiKey object
cb.authenticate auth = new cb.authenticate();
auth.apiKey = "YOUR_API_KEY";
//A single invoice
cb.Invoice invExample = new cb.Invoice();
invExample.dateCreated = "2012-01-24";
invExample.dateDue = "";
invExample.description = "My C# test invoice";
invExample.reference = "1234";
invExample.type ="purchases";
invExample.entityId = 1;
cb.Item line = new cb.Item();
line.description ="Standard Monthly Plan 15 inc VAT";
line.unitPrice = (float) 12.0;
line.quantity = (int) 12.0;
line.type =2001003;
line.vatRate = "0.2";
invExample.items = new cb.Item[1];
invExample.items[0] = line;
richTextBox1.AppendText("Request Start");
//Creating an invoice using a call to the client
cb.Invoice response = client.createInvoice(auth, invExample);
richTextBox1.AppendText("Request Complete");
}
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