(SQL Server) Duplicating a Simple HTML Form Submission (POST)

This example shows how to duplicate a simple HTML form submission. The HTML to be duplicated is shown below, and may be tested in a browser by going to this URL: http://www.chilkatsoft.com/postSample.html


<html>
<body>
<form action="echoPost.asp" method="post">
<p>First name: <input name="firstname"></p>
<p>Last name: <input name="lastname"></p>
<p>Your favorite color:
<select name="color">
<option>Blue</option>
<option>Green</option>
<option>Red</option>
<option>Yellow</option>
<option>Pink</option>
</select>
</p>
<input type="hidden" name="myHiddenField1", value="Hidden Value 1">
<input type="hidden" name="myHiddenField2", value="Hidden Value 2">
<p><input type="submit" value="Send POST"></p>
</form>

</body>
</html>

By default, a browser will send a form POST as an HTTP reqeuest using a Content-Type of "application/x-www-form-urlencoded". This is because the form parameters are sent in the body of the HTTP POST using the URL encoding. Therefore, one should use the PostUrlEncoded method to duplicate the form submission.

Each "input" or "select" tag found in the HTML is a form parameter having a name and value. These are duplicated in code by calling AddParam on the HTTP Request object for each parameter.

The target URL is indicated by the "action" attribute on the "form" tag. In the HTML form shown above, it is "echoPost.asp". The URL specified in the "action" attribute may be an absolute or relative URL. In this case, it is a relative URL, and since there is no directory path, the full URL of the POST target is "http://www.chilkatsoft.com/echoPost.asp". This will be the 1st argument passed to the PostUrlEncoded method.

The raw HTTP POST sent to the web server in this example is shown below. The form parameters are located in the body of the request (i.e. under the header fields), and they are URL encoded.

POST /echoPost.asp HTTP/1.1
Content-Type: application/x-www-form-urlencoded
Host: www.chilkatsoft.com
Content-Length: 87

firstname=John&lastname=Doe&myHiddenField1=Hidden+Value+1&myHiddenField2=Hidden+Value+2

Note: An HTTP file upload is a form submission having an "input" tag w/ "type=file". In this case, a browser will send the POST using a content-type of "multipart/form-data". The PostUrlEncoded method should not be called for HTTP file uploads. The SynchronousRequest would instead be called.

Download Chilkat HTTP ActiveX

CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @http int
    EXEC @hr = sp_OACreate 'Chilkat.Http', @http OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @success int

    --  Any string unlocks the component for the 1st 30-days.
    EXEC sp_OAMethod @http, 'UnlockComponent', @success OUT, 'Anything for 30-day trial'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @http, 'LastErrorText', @sTmp0 OUT

        PRINT @sTmp0
        RETURN
      END

    DECLARE @request int
    EXEC @hr = sp_OACreate 'Chilkat.HttpRequest', @request OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    --  Add the form parameters to the HTTP request:
    EXEC sp_OAMethod @request, 'AddParam', NULL, 'firstname', 'John'
    EXEC sp_OAMethod @request, 'AddParam', NULL, 'lastname', 'Doe'
    EXEC sp_OAMethod @request, 'AddParam', NULL, 'myHiddenField1', 'Hidden Value 1'
    EXEC sp_OAMethod @request, 'AddParam', NULL, 'myHiddenField2', 'Hidden Value 2'

    --  Send the HTTP POST by calling PostUrlEncoded.
    --  The Content-Type used w/ the request will be application/x-www-form-urlencoded
    DECLARE @response int

    EXEC sp_OAMethod @http, 'PostUrlEncoded', @response OUT, 'http://www.chilkatsoft.com/echoPost.asp', @request
    IF @response Is NULL 
      BEGIN
        EXEC sp_OAGetProperty @http, 'LastErrorText', @sTmp0 OUT

        PRINT @sTmp0
        RETURN
      END

    --  Display the Body of the HTTP response
    --  (This is the HTML that the browser would receive if it
    --  had been an interactive form submission from the browser.)
    EXEC sp_OAGetProperty @response, 'BodyStr', @sTmp0 OUT

    PRINT @sTmp0


END
GO