c# - SetAttribute not working in WebBrowser Control -

c# - SetAttribute not working in WebBrowser Control -

i developing automation windows application in c# using web browser control. set values controls, using setattribute property. works fine controls text box consist watermarking

for example

the next coding

webbrowser.document.getelementbyid("ctl00_content1_dob_txbx").setattribute("value", "09/17/1976");

while running application, textbox holds value watermarking

for example

while clicking submit button date getting vanish. how can set date in watermarking text box?

how can accomplish next output

note: in website watermark achieved ajax watermarkextender

i have found solution have set value in webbrowser_progresschanged event works fine

private void automationwebbrowser_progresschanged(object sender, webbrowserprogresschangedeventargs e) { if (automationwebbrowser.document.getelementbyid("ctl00_content1_dob_txbx") != null) automationwebbrowser.document.getelementbyid("ctl00_content1_dob_txbx").setattribute("value", "09/17/1976"); }

c# browser setattribute