We recently had a client who wanted to have a user confirmation prompt before a user was allowed to make a change to a dependency lookup. This was because there were rules in place that significantly altered data upon a value being changed from one thing to another. The particular control that this was for was the Dependency Lookup control. Normally this control does not have any kind of confirmation message but by examining the elements in the DOM I was able to figure out how to do it by injecting client side code on the page load. lets take a look at the script I used:
string script = “function confirmChange() { ”
script += “return confirm(‘Changing this will cause something really neat to happen. Click OK if you want to continue.’);} ”
script += “document.getElementById(‘” + dplArea.ClientID + “_Area_ShowBtn‘).setAttribute(‘onclick’,’return false;’);”;
script += “var dpLookup = $(‘#” + dplArea.ClientID + “_Area_ShowBtn‘);”
script += “dpLookup.unbind(‘click’);dpLookup.click(function() { if (!confirmChange()) { ”
script += “document.getElementById(‘” + dplArea.ClientID + “_Area_ShowBtn‘).setAttribute(‘onclick’,’return false;’); } ”
script += “else document.getElementById(‘” + dplArea.ClientID + “_obj”‘).Show()});”
ScriptManager.RegisterStartupScript(Page, GetType(), “FXCheckProduct”, script, true);
There are several highlighted bits. In my case my lookup control was called dplArea so I added that control’s client ID into the script in the various places. The other highlighted bits “_Area_ShowBtn”, in conjunction with the client ID, is the DOM for the actual button of the lookup. Since the top level lookup in the Dependency Lookup was named Area, that is why it is called “_Area_ShowBtn”. You can examine your control on the page to see what your particular control is named.
The important thing to note here is I first remove the normal click action of the control using the first lline like this:
script += “document.getElementById(‘” + dplArea.ClientID + “_Area_ShowBtn’).setAttribute(‘onclick’,’return false;’);”;
This is so that after the confirmation, the normal popup of the lookup doesn’t occur.
The other thing to note is that I am using the unbind method to remove all previous click actions. This is because otherwise, you end up getting your confirmation message re-added each time a postback happens, causing the user to get prompted over and over once they do click the button:
script += “dpLookup.unbind(‘click’);dpLookup.click(function() { if (!confirmChange()) { ”
Finally the whole script is added to the page using the RegisterStartupScript. This code was added as a C# code snippet on the quick form’s load event, making sure the OnRepaint event is set to True.
