get text vaule of dropdownlist client side
I am trying to add a client side event to a dropdownlist and I need to access the currently selected Text. I have tried:
ddl_tech.Attributes.Add("onclick", "document.getElementById('" + chk_techreview.ClientID + "').disabled = this.options[this.selectedIndex].text.Equals(' UNASSIGNED');");
and
ddl_tech.Attributes.Add("onclick", "document.getElementById('" + chk_techreview.ClientID + "').disabled = this.text.Equals(' UNASSIGNED');");
Both of which give me runtime errors when the event is fired.
Whats the correct way to access this text property client side?
I tried this but it does not enable the checkbox...
ddl_tech.Attributes.Add("onchange", "document.getElementById('" + chk_techrev开发者_运维技巧iew.ClientID + "').disabled = this.options[this.selectedIndex].text == ' UNASSIGNED';");
ANSWER:
Well, along with having to use == rather than .Equals, when you set a checkbox.enabled = false on the server side it raps the checkbox in tags and sets it to disabled=true; therefore you must set BOTH the checkbox.disabled = false and checkbox.parentElement.disabled = false; on the client side to enable the checkbox!
The solution:
ddl_tech.Attributes.Add("onchange", "document.getElementById('" + chk_techreview.ClientID + "').parentElement.disabled = (this.options[this.selectedIndex].text == 'UNASSIGNED'); document.getElementById('" + chk_techreview.ClientID + "').disabled = (this.options[this.selectedIndex].text == 'UNASSIGNED');");
Thanks for the help!
There is no .Equals()
on a string in JavaScript, instead use the ===
operator, like this:
ddl_tech.Attributes.Add("onchange", "document.getElementById('chk_techreview').disabled = ( this.options[this.selectedIndex].text === 'UNASSIGNED');");
You can give it a try here, I also changed the event to onchange
since that's probably more of what you're after. Also, depending on your option it may just be 'UNASSIGNED'
rather than ' UNASSIGNED'
.
I believe it should be:
ddl_tech.Attributes.Add("onclick", "var s = document.getElementById('" + chk_techreview.ClientID + "'); s.disabled = (s.selectedIndex == -1 || s.options[s.selectedIndex].text == ' UNASSIGNED ');");
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