App_Code.Controls.RecaptchaControl.RenderContents C# (CSharp) Method

        protected override void RenderContents(HtmlTextWriter output)
        {
            output.AddAttribute("type", "text/javascript");
            output.AddAttribute("src", "http://api.recaptcha.net/js/recaptcha_ajax.js");
            output.RenderBeginTag("script");
            output.RenderEndTag();

            output.AddAttribute(HtmlTextWriterAttribute.Id, "spnCaptchaIncorrect");
            output.AddAttribute(HtmlTextWriterAttribute.Style, "color:Red;display:none;");
            output.RenderBeginTag("span");
            output.WriteLine("The captcha text was not valid. Please try again.");
            output.RenderEndTag();

            output.AddAttribute(HtmlTextWriterAttribute.Id, "recaptcha_placeholder");
            output.RenderBeginTag(HtmlTextWriterTag.Div);
            output.RenderEndTag();

            output.AddAttribute(HtmlTextWriterAttribute.Type, "text/javascript");
            output.RenderBeginTag(HtmlTextWriterTag.Script);
            output.WriteLine("function showRecaptcha() {");
            output.WriteLine("Recaptcha.create('{0}', 'recaptcha_placeholder', {{", this.publicKey);
            output.WriteLine("theme: '{0}',", this.Theme);
            output.WriteLine("lang: '{0}',", this.Language);
            output.WriteLine("tabindex: {0}", this.TabIndex);
            output.WriteLine("})");
            output.WriteLine("}");

            output.WriteLine("var rc_oldonload = window.onload;");
            output.WriteLine("if (typeof window.onload != 'function') {");
            output.WriteLine("window.onload = showRecaptcha;");
            output.WriteLine("}");
            output.WriteLine("else {");
            output.WriteLine("window.onload = function() {");
            output.WriteLine("rc_oldonload();");
            output.WriteLine("showRecaptcha();");
            output.WriteLine("}");
            output.WriteLine("}");

            output.RenderEndTag();
        }