尝试生成pdf时间歇性地收到错误消息

Question

错误消息看起来像“无法呈现网址。无法从url.Navigation超时获取图像..”

我得到的堆栈跟踪放在下面。

  

2016-01-04 12：01：04,684 [57]错误   ErrorID中= '0ece54f2-8232-4c1e-9854-c81f6a8ffa57'，   ExceptionMessage ='类型异常   抛出'System.Web.HttpUnhandledException'。'，   ExceptionStacktrace ='at System.Web.UI.Page.HandleError（Exception e）   在System.Web.UI.Page.ProcessRequestMain（布尔值   includeStagesBeforeAsyncPoint，Boolean includeStagesAfterAsyncPoint）
  在System.Web.UI.Page.ProcessRequest（布尔值   includeStagesBeforeAsyncPoint，Boolean includeStagesAfterAsyncPoint）
  在System.Web.UI.Page.ProcessRequest（）处   System.Web.UI.Page.ProcessRequest（HttpContext context）at   System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute（）   在System.Web.HttpApplication.ExecuteStep（IExecutionStep步骤，   布尔和放大器; completedSynchronously）”。   Winnovative.WnvHtmlConvert.HtmlConvertException：无法渲染   网址。无法从url.Navigation超时...获取图像   Winnovative.WnvHtmlConvert.ImgConverter.GetMetafileFromUrl（String url，   十一＆安培; htmlParseInfo）at   Winnovative.WnvHtmlConvert.PdfConverter.ConvertAndGetPdfDocument（字符串   url，String htmlString，String baseUrl，String internalLinksDocUrl，   布尔fromUrl）at   Winnovative.WnvHtmlConvert.PdfConverter.ConvertAndSaveToStream（流   outStream，String url，String htmlString，String baseUrl，String   internalLinksDocUrl，Boolean fromUrl）at   Winnovative.WnvHtmlConvert.PdfConverter.GetPdfBytes（String url，String   htmlString，String baseUrl，String internalLinksDocUrl，Boolean   fromUrl）at   Winnovative.WnvHtmlConvert.PdfConverter.GetPdfBytesFromUrl（String url）   at Metrica.results.btnExportCertificates_Click（Object sender，   EventArgs e）in   e：\ Build \ Work \ 593ad3cfd51af9bc \ Metrica \ results.aspx.cs：第612行   System.Web.UI.WebControls.Button.RaisePostBackEvent（字符串   event.Web.UI.Page.ProcessRequestMain的EventArgument（布尔值   includeStagesBeforeAsyncPoint，Boolean includeStagesAfterAsyncPoint）

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.0.0/jquery.min.js">
</script>
<fieldset>
<legend>Client Details</legend>

<table class="nobord"><tr> 
    <td>Type:</td>
	<td>Landlord </td>
  </tr><tr> 
    <td>Name:</td>
	<td>Mr XXX</td>
  </tr><tr> 
    <td>Client Bank Account Balance:</td>
	<td>&pound;387.68</td>
  </tr></table>

</fieldset><fieldset>
<legend>Outstanding Invoice Details</legend><table class="solid" style="margin:5px;"><tr>
    <th>Invoice #</th>
    <th>Date</th>
	<th>Due Date</th>
    <th>Invoice Total</th>
    <th>Amount Paid</th>
	<th>Amount Due</th>
	<th>Amount Received (&pound;)</th>
  </tr><tr>
    <td><a href="view_invoice.php?invoice_id=496" target="_blank">496</a>
	<input type="text" class="invoice_reference" value="496">
	</td>
    <td>14/01/16</td>
	<td>14/01/16</td>
    <td>&pound;25.20</td>
    <td>&pound;0.00</td>
	<td>&pound;25.20
	<input type="hidden" name="amount_outstanding[]" value="25.20">
	</td>
	<td>
	<input type="number" name="amount_received[]" class="amount_received" value="0.00" max="25.20" required>&nbsp;<button class="pay_in_full" type="button">Pay in Full</button>
	<input type="hidden" name="invoice_id[]" value="496">
	<input type="hidden" name="invoice_tenancy_id[]" value="40">
	<input type="hidden" name="invoice_property_id[]" value="119"></td>

  </tr>
<tr>
    <td><a href="view_invoice.php?invoice_id=497" target="_blank">497</a>
	<input type="text" class="invoice_reference" value="497">
	</td>
    <td>14/01/16</td>
	<td>14/01/16</td>
    <td>&pound;25.20</td>
    <td>&pound;0.00</td>
	<td>&pound;25.20
	<input type="hidden" name="amount_outstanding[]" value="25.20">
	</td>
	<td>
	<input type="number" name="amount_received[]" class="amount_received" value="0.00" max="25.20" required>&nbsp;<button class="pay_in_full" type="button">Pay in Full</button>
	<input type="hidden" name="invoice_id[]" value="497">
	<input type="hidden" name="invoice_tenancy_id[]" value="40">
	<input type="hidden" name="invoice_property_id[]" value="119"></td>

  </tr></table></fieldset>
<fieldset>
<legend>Payment Details</legend>

<table class="nobord"><tr> 
    <td><label for="invoice_payment_date">Date:</label></td>
	<td>
	<input type="date" id="invoice_payment_date" name="invoice_payment_date" class="datepicker2months" ondblclick="this.value='2016-01-14';" readonly required>
	</td>
  </tr><tr> 
    <td><label for="total_amount_received">Total Amount Received (&pound;):</label></td>
	<td>
	<input type="number" id="total_amount_received" name="total_amount_received" readonly required>
	<input type="hidden" id="client_bank_account_balance" name="client_bank_account_balance" value="387.68" required>
	</td>
  </tr><tr> 
    <td><label for="payment_reference">Payment Reference:</label></td>
	<td>
	<input type="text" id="payment_reference" readonly>&nbsp;<button id="generate_payment_reference" type="button">Generate</button>
	</td>
  </tr><tr>
    <td><label for="invoice_payment_use_balance">Pay from Client Bank Account Balance:</label></td>
	<td><select id="invoice_payment_use_balance" name="invoice_payment_use_balance" required><option value="">Please Select</option><option value="0">No</option><option value="1" selected>Yes</option></select></td></tr><tr>
    <td><label for="invoice_payment_method">Method:</label></td>
	<td><select id="invoice_payment_method" name="invoice_payment_method" required><option value="">Please Select</option><option value="2" selected>Bank Transfer</option><option value="1">Cash</option><option value="3">Cheque</option><option value="4">Credit Card</option><option value="5">Debit Card</option></select></td></tr><tr>
    <td><label for="invoice_payment_notes">Notes:</label></td>
	<td><textarea id="invoice_payment_notes" name="invoice_payment_notes" rows="6" cols="40"></textarea></td></tr></table>

</fieldset>