JS：根据条件在for循环内分配变量值

Question

I need to add

if (obj1[i][0] !== d1 && row > -1) continue;

and

if (obj1[i][1] !== d2 && row > -1) continue;

depending on the value of d1 and d2 but I'm not sure what I'm doing wrong.

if statement acts as a filter it will allow only those values which assigned to d1 or d2 eg if d1=1 it will print only values with 1 and not all values in the table.

$("#session_id, #start_date").on('change', function() {
    var d1 = $( "#session_id" ).val();
    var d2 = $( "#start_date" ).val();

    $("#tbody").empty();


    if(d1 != null || d1 != undefined){
        kl1 = "if (obj1[i][0] !== d1 && row > -1) continue;";
        v(kl1);
    }

    if(d2 != null || d2 != undefined){
        var kl = "if (obj1[i][1] !== d2 && row > -1) continue;"
        v(kl);
    }

    function v(data){
        for (var i = 0; i < obj1.length; i++) {
                data;
            row++;
        var newTr = table.insertRow(-1);
        newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][1]));
        newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][2]));
        newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][3]));
        newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][4]));
        newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][5]));
    }
}
});

Answer 1

I think, this is what you want. The way you're thinking to pass statement to loop actually doesn't work.

We can simplify the following code

d1 != null || d1 != undefined

by using javascript truthy & falsey

See the code below:

$("#session_id, #start_date").on('change', function() {
    var d1 = $( "#session_id" ).val();
    var d2 = $( "#start_date" ).val();

    $("#tbody").empty();

    for (var i = 0; i < obj1.length; i++) {
        if (d1 && obj1[i][0] !== d1 && row > -1) continue;
        if (d2 && obj1[i][1] !== d2 && row > -1) continue;
        row++;
        var newTr = table.insertRow(-1);
        newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][1]));
        newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][2]));
        newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][3]));
        newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][4]));
        newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][5]));
    }
});

Answer 2

Just remove statements out of the values and convert it to Boolean and pass it to the function

if(d1 != null || d1 != undefined){
        kl1 = obj1[i][0] !== d1 && row > -1
        v(kl1);
    }

    if(d2 != null || d2 != undefined){
        var kl = obj1[i][1] !== d2 && row > -1
        v(kl);
    }

    function v(data){
        for (var i = 0; i < obj1.length; i++) {
                if(data) continue;
            row++;
            var newTr = table.insertRow(-1);
            newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][1]));
            newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][2]));
            newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][3]));
            newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][4]));
            newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][5]));
        }
    }

Answer 3

The assignment that you are giving for k1 is string. Thats why instead of passing continue it is passing the whole statement. Please find below the way you can do.

if(d1 != null || d1 != undefined){
    if (obj1[i][0] !== d1 && row > -1) kl = "true";
    v(kl);
}

if(d2 != null || d2 != undefined){
    if (obj1[i][1] !== d2 && row > -1) kl =  "true"
    v(kl);
}

function v(data){
    for (var i = 0; i < obj1.length; i++) {
            if(data=="true") continue
        row++;
    var newTr = table.insertRow(-1);
    newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][1]));
    newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][2]));
    newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][3]));
    newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][4]));
    newTr.insertCell(-1).appendChild(document.createTextNode(obj1[i][5]));
}