How to programmatically click on text input in WebBrowser using C#

I have opened a website using WebBrowser. Now I would like to programmatically click input text (textbox) field. I can not use focus because this website uses JS to unlock this field only if it's clicked and I've tried also this:

Object obj = ele.DomElement;
System.Reflection.MethodInfo mi = obj.GetType().G开发者_开发百科etMethod("click");
mi.Invoke(obj, new object[0]); 

But it returns mi = null. How to do this so it will work?

Very similar to my answer on your other question.

Get an HtmlElement respresentative of your textbox, and call HtmlElement.InvokeMember("click") on it.

If you can, use:

webbrowser1.Navigate("javascript:document.forms[0].submit()")

or something similar. For me, it's been much easier and more accurate.

To fill-up a text field on a webpage:

string code ="";
code = code + "var MyVar=document.getElementById('tbxFieldNameOnWebPage');if(MyVar != null) MyVar.value = 'SOMEVALUE';";
domDocument.parentWindow.execScript(code, "JScript");

Then To Click a button on a webpage:

code = "";
code = "var SignupFree = document.getElementsByTagName('button')[1];";
code = (code + " SignupFree.click();");
domDocument.parentWindow.execScript(code, "JScript");

you can also use document.getElementById('buttonID'); instead of document.getElementsByTagName('button')[1]; but an id must be provided for this button on that particular webpage.

Use InvokeMethhod on HtmlElement or Browser.InvokeScript function.