I am working on a web scraper in C# where I have a web browser control that loads a web page, I then collect data and depending on the data also acting on it. My problem is that I need to write some data to a input (textbox) that has listeners. The input control never shows a value in the html, it is handled by some Javascript that is fired from events on the control. I can set a value to the controls value parameter but it is as it is missing when I click OK on the form.
I have searched the web for days and I now know how to call Javascript from C# but it's the Javascript function on the input i cannot understand.
The input control looks like this:
<div id="size_1" class="incrementControl" style="width: 68px;">
<input id="size_1-input" class="hasListeners" maxlength="6" tabindex="103" value="" style="width:52px">
<a id="size_1-up" class="up hasListeners" style="left:52px" href="javascript:void(0)"> </a>
<a id="size_1-down" class="down hasListeners" style="left:52px" href="javascript:void(0)"> </a>
</div>
The input controls event keyup, keydown, change, keypress and blur all call this Javascript:
function (a)
{
return typeof f != "undefined" && (!a || f.event.triggered !== a.type) ? f.event.dispatch.apply(i.elem, arguments) : b;
}
I have tried invoking different events like onClick and clicking the control programmatically but nothing works?! I don´t know how to call this Javascript function since it doesn't have a name and what to pass as a parameter?
Most grateful for any help or ideas!
You can use Watin . It support Webbrowser control and Internet Explorer.
Here are a number of extension methods (built on top of WatiN) that allow you to (amongst other things) to wait for JS objects or events:
using System;
using System.Threading;
using FluentSharp.Web35;
using FluentSharp.WinForms;
using FluentSharp.CoreLib;
using FluentSharp.CoreLib.API;
namespace FluentSharp.Watin
{
public static class WatiN_IE_ExtensionMethods_Javascript
{
public static object invokeScript(this WatiN_IE ie, string functionName)
{
return ie.invokeScript(functionName, null);
}
public static object invokeScript(this WatiN_IE ie, string functionName, params object[] parameters)
{
//"[WatiN_IE] invokeScript '{0}' with parameters:{1}".info(functionName ,parameters.size());
return ie.invokeScript(true, functionName, parameters);
}
public static object invokeScript(this WatiN_IE ie, bool waitForExecutionComplete, string functionName, params object[] parameters)
{
var sync = new AutoResetEvent(false);
object responseValue = null;
ie.WebBrowser.invokeOnThread(
()=>{
var document = ie.WebBrowser.Document;
if (parameters.isNull())
responseValue = document.InvokeScript(functionName);
else
responseValue = document.InvokeScript(functionName, parameters);
sync.Set();
});
if (waitForExecutionComplete)
sync.WaitOne();
return responseValue;
}
public static object invokeEval(this WatiN_IE ie, string evalScript)
{
var evalParam = "(function() { " + evalScript + "})();";
//"[WatiN_IE] invokeEval evalParam: {0}".debug(evalParam);
return ie.invokeScript("eval", evalParam);
}
public static WatiN_IE.ToCSharp injectJavascriptFunctions(this WatiN_IE ie)
{
return ie.injectJavascriptFunctions(false);
}
public static WatiN_IE.ToCSharp injectJavascriptFunctions(this WatiN_IE ie, bool resetHooks)
{
if (ie.WebBrowser.isNull())
"in InjectJavascriptFunctions, ie.WebBrowser was null".error();
else
{
if (ie.WebBrowser.ObjectForScripting.isNull() || resetHooks)
{
ie.WebBrowser.ObjectForScripting = new WatiN_IE.ToCSharp();
"Injecting Javascript Hooks * Functions for page: {0}".debug(ie.url());
ie.eval("var o2Log = function(message) { window.external.write(message) };");
ie.invokeScript("o2Log","Test from Javascript (via toCSharp(message) )");
ie.eval("$o2 = window.external");
"Injection complete (use o2Log(...) or $o2.write(...) to talk back to O2".info();
return (ie.WebBrowser.ObjectForScripting as WatiN_IE.ToCSharp);
}
else
{
if((ie.WebBrowser.ObjectForScripting is WatiN_IE.ToCSharp))
return (ie.WebBrowser.ObjectForScripting as WatiN_IE.ToCSharp);
else
"in WatiN_IE injectJavascriptFunctions, unexpected type in ie.WebBrowser.ObjectForScripting: {0}".error(ie.WebBrowser.ObjectForScripting.typeName());
}
}
return null;
}
public static object downloadAndExecJavascriptFile(this WatiN_IE ie, string url)
{
"[WatiN_IE] downloadAndExecJavascriptFile: {0}".info(url);
var javascriptCode = url.uri().getHtml();
if (javascriptCode.valid())
ie.eval(javascriptCode);
return ie;
}
public static WatiN_IE injectJavascriptFunctions_onNavigate(this WatiN_IE ie)
{
ie.onNavigate((url)=> ie.injectJavascriptFunctions());
return ie;
}
public static WatiN_IE setOnAjaxLog(this WatiN_IE ie, Action<string, string,string,string> onAjaxLog)
{
(ie.WebBrowser.ObjectForScripting as WatiN_IE.ToCSharp).OnAjaxLog = onAjaxLog;
return ie;
}
public static WatiN_IE eval_ASync(this WatiN_IE ie, string script)
{
O2Thread.mtaThread(()=> ie.eval(script));
return ie;
}
public static WatiN_IE eval(this WatiN_IE ie, string script)
{
return ie.eval(script, true);
}
public static WatiN_IE eval(this WatiN_IE ie, string script, bool waitForExecutionComplete)
{
var executionThread = O2Thread.staThread(()=> ie.IE.RunScript(script));
if (waitForExecutionComplete)
executionThread.Join();
return ie;
}
public static WatiN_IE alert(this WatiN_IE ie, string alertScript)
{
return ie.eval("alert({0});".format(alertScript));
}
public static object getJsObject(this WatiN_IE ie)
{
var toCSharpProxy = ie.injectJavascriptFunctions();
if (toCSharpProxy.notNull())
return toCSharpProxy.getJsObject();
return null;
}
public static T getJsObject<T>(this WatiN_IE ie, string jsCommand)
{
var jsObject = ie.getJsObject(jsCommand);
if (jsObject is T)
return (T)jsObject;
return default(T);
}
public static bool doesJsObjectExists(this WatiN_IE ie, string jsCommand)
{
var toCSharpProxy = ie.injectJavascriptFunctions();
if (toCSharpProxy.notNull())
{
var command = "window.external.setJsObject(typeof({0}))".format(jsCommand);
ie.invokeEval(command);
ie.remapInternalJsObject();
return toCSharpProxy.getJsObject().str()!="undefined";
}
return false;
}
public static object getJsVariable(this WatiN_IE ie, string jsCommand)
{
return ie.getJsObject(jsCommand);
}
public static object getJsObject(this WatiN_IE ie, string jsCommand)
{
var toCSharpProxy = ie.injectJavascriptFunctions();
if (toCSharpProxy.notNull())
{
var command = "window.external.setJsObject({0})".format(jsCommand);
ie.invokeEval(command);
ie.remapInternalJsObject();
return toCSharpProxy.getJsObject();
}
return null;
}
public static WatiN_IE remapInternalJsObject(this WatiN_IE ie)
{
//"setting JS _jsObject variable to getJsObject()".info();
ie.invokeEval("_jsObject = window.external.getJsObject()"); // creates JS variable to be used from JS
return ie;
}
public static WatiN_IE setJsObject(this WatiN_IE ie, object jsObject)
{
var toCSharpProxy = ie.injectJavascriptFunctions();
if (toCSharpProxy.notNull())
{
toCSharpProxy.setJsObject(jsObject);
ie.remapInternalJsObject();
}
return ie;
}
public static object waitForJsObject(this WatiN_IE watinIe)
{
return watinIe.waitForJsObject(500, 20);
}
public static object waitForJsObject(this WatiN_IE watinIe, int sleepMiliseconds, int maxSleepTimes)
{
"[WatiN_IE][waitForJsObject] trying to find jsObject for {0} x {1} ms".info(maxSleepTimes, sleepMiliseconds);
watinIe.setJsObject(null);
for(var i = 0; i < maxSleepTimes ; i++)
{
var jsObject = watinIe.getJsObject();
if(jsObject.notNull())
{
"[watinIe][waitForJsObject] got value: {0} (n tries)".info(jsObject, i);
return jsObject;
}
watinIe.sleep(500, false);
}
"[WatiN_IE][waitForJsObject] didn't find jsObject after {0} sleeps of {1} ms".error(maxSleepTimes, sleepMiliseconds);
return null;
}
public static object waitForJsVariable(this WatiN_IE watinIe, string jsCommand)
{
return watinIe.waitForJsVariable(jsCommand, 500, WatiN_IE_ExtensionMethods.WAITFORJSVARIABLE_MAXSLEEPTIMES);
}
public static object waitForJsVariable(this WatiN_IE watinIe, string jsCommand, int sleepMiliseconds, int maxSleepTimes)
{
"[WatiN_IE][waitForJsVariable] trying to find jsObject called '{0}' for {1} x {2} ms".info(jsCommand, maxSleepTimes, sleepMiliseconds);
watinIe.setJsObject(null);
for(var i = 0; i < maxSleepTimes ; i++)
{
if (watinIe.doesJsObjectExists(jsCommand))
{
var jsObject = watinIe.getJsObject(jsCommand);
"[watinIe][waitForJsVariable] got value: {0} ({1} tries)".info(jsObject, i);
return jsObject;
}
watinIe.sleep(500, false);
}
"[WatiN_IE][waitForJsVariable] didn't find jsObject called '{0}' after {1} sleeps of {2} ms".error(jsCommand, maxSleepTimes, sleepMiliseconds);
return null;
}
public static WatiN_IE deleteJsVariable(this WatiN_IE watinIe, string jsVariable)
{
var evalString = "try { delete " + jsVariable + " } catch(exception) { }";
watinIe.eval(evalString);
return watinIe;
}
}
}
See https://github.com/o2platform/FluentSharp_Fork.WatiN/tree/master/FluentSharp.WatiN/ExtensionMethods for many more WatiN/WebBroser Extension Methods
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