从项目数组中删除项目

Question

I have list of variables/items

dbTemp = [Type,Threshold,TypeID,Prioirty,Value,Assign]

where Type,Threshold,TypeID,Prioirty are variables Let's say, their values are 1,0,2,0,NULL,21

If a variable value is 0 or NULL , I need to remove/exclude them from the list and build a dynamic variable expression based on the non-zero or non-NULL values

In this case, Dynamic Expression = Type>0+TypeID>0+Assign>0 (excludes Threshold , Priority , Value variables since their values are 0 or NULL )

Can you please help me here?

Answer 1

filtered here:

var filtered = dbTemp.filter( function(el) { return !!el; } );

will contain all non null or zero elements from dbTemp;

Answer 2

If you want to filter based on some condition(s) instead of just filtering falsy values:

var filtered = orignalArray.filter(function(item) {
    return (item !== condition1) && (item !== condition2);
});

ps NULL !== null

Answer 3

If you'll allow for any falsey value and a result that is a filtered copy, then this will suffice:

var result = dbTemp.filter(Boolean);

---

If you actually need to mutate the original and order doesn't matter, then do this:

for (var i = 0; i < dbTemp.length; i++) {
    if (!dbTemp[i]) {
        dbTemp[i] = dbTemp[dbTemp.length-1];
        dbTemp.length--;
        i--;
    }
}

---

If the original order does matter, then this:

for (var i = 0; i < dbTemp.length; i++) {
    if (!dbTemp[i]) {
        dbTemp[i].splice(i, 1);
        i--;
    }
}