<td class="bz"> </bz>
js
$(".bz").each(function(i,n){
var obj = $(n);
var val = obj.text();
alert(val);
if(val == "" || val == null || val == undefined){
alert(val);
wglx += "null,";
}else{
wglx += obj.text() + ",";
}
}); if (val = =""| | val = = null | | val = = undefined)
this sentence has no effect
and if there is a value, alert will not be executed at all
cannot be judged
