c# - Trying to get my head wrapped around Conditional NULL syntax -


i've got asp.net search page displays sql bound listview after search button clicked. in emptydatatemplate, i've got asp label based on id searched in message. "no results found " kinda thing.

here's original codebehind button click:

protected void btnsearch_command(object sender, commandeventargs e) {      label lbl = (label)lvmatorders.controls[0].controls[0].findcontrol("lblprojectid");     if (lbl != null)  // means emptydatatemplate used, else itemtemplate     {          if (string.isnullorempty(txtprojectid.text))         {             lbl.text = "#####";         }         else         {             lbl.text = txtprojectid.text;         }      } }

am correct in understanding can reduce down following?

label lbl = (label)lvmatorders.controls[0].controls[0].findcontrol("lblprojectid"); lbl?.text = (string.isnullorempty(txtprojectid.text)) ? "#####" : txtprojectid.text;

the main goal here make sure code attempts assign either "#####" or txtprojectid.text lbl.text doesn't executed if page has results previous search displayed page isn't showing emptydatatemplate , no lblprojectid assign text to.

will lbl?.text line attempted if page in itemtemplate mode?

no, code not compile, error "the left-hand side of assignment must variable, property or indexer"

you can not use .? operator on left hand side of equals sign, right hand side.


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