对于循环退出之前，我希望它

Question

好的，所以我有2个阵列，一个由20支球队组成，一个由联赛装备组成。 然后，我有一个非常大的for循环，该循环遍历每个固定装置，并为每个团队分配分数，得分，允许的目标等。 只要夹具阵列中的夹具不超过20个，一切就可以正常工作。 一旦将第21个固定装置放入数组中，我的桌子就会崩溃，我不确定为什么。

var teams = [
 {id: 1, name: "AC Milan", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 2, name: "AS Roma", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 3, name: "Atalanta", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 4, name: "Bologna", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 5, name: "Benevento", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 6, name: "Cagliari", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 7, name: "Chievo", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 8, name: "Crotone", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 9, name: "Fiorentina", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 10, name: "Genoa", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 11, name: "Hellas Verona", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 12, name: "Inter", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 13, name: "Juventus", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 14, name: "Lazio", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 15, name: "Napoli", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 16, name: "Sampdoria", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 17, name: "Sassuolo", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 18, name: "SPAL", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
 {id: 19, name: "Torino", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
{id: 20, name: "Udinese", GP:0, W: 0, D: 0, L:0, GF:0, GA:0, pts:0},
];


var fixtures = [
//matchday1
{match: 1, Homeid: 13, Awayid: 6,    Homescore: 3, Awayscore: 0},
{match: 1, Homeid: 11, Awayid: 15,    Homescore: 1, Awayscore: 3},
{match: 1, Homeid: 3,  Awayid: 2,    Homescore: 0, Awayscore: 1},
{match: 1, Homeid: 14, Awayid: 18,   Homescore: 0, Awayscore: 0},
{match: 1, Homeid: 4,  Awayid: 19,   Homescore: 1, Awayscore: 1},
{match: 1, Homeid: 12, Awayid:9,     Homescore: 3, Awayscore: 0},
{match: 1, Homeid: 20, Awayid: 7,    Homescore: 1, Awayscore: 2},
{match: 1, Homeid: 16, Awayid: 5,   Homescore: 2, Awayscore: 1},
{match: 1, Homeid: 17, Awayid: 10,   Homescore: 0, Awayscore: 0},
{match: 1, Homeid: 8, Awayid: 1,   Homescore: 0, Awayscore:3 },
//matchday2
{match: 1, Homeid: 10, Awayid: 13,    Homescore: 2, Awayscore: 4},
{match: 1, Homeid: 5, Awayid: 4,    Homescore: 0, Awayscore: 1},
{match: 1, Homeid: 2,  Awayid: 12,    Homescore: 1, Awayscore: 3},
{match: 1, Homeid: 19, Awayid: 17,   Homescore: 3, Awayscore: 0},
{match: 1, Homeid: 1,  Awayid: 6,   Homescore: 2, Awayscore: 1},
{match: 1, Homeid: 7, Awayid:14,     Homescore: 1, Awayscore: 2},
{match: 1, Homeid: 9, Awayid: 16,    Homescore: 1, Awayscore: 2},
{match: 1, Homeid: 8, Awayid: 11,   Homescore: 0, Awayscore: 0},
{match: 1, Homeid: 15, Awayid: 3,   Homescore: 3, Awayscore: 1},
{match: 1, Homeid: 18, Awayid: 20,   Homescore: 3, Awayscore: 2}

]。

for (var i = 0; i < fixtures.length;i++)      //For loop which calculates the Home and Away results for each team
{  
    if (fixtures[i].Homeid == 1)
    {
        for (var j = 0; j <teams.length; j++)
        {
            if (teams[j].id == fixtures[i].Homeid)
                {
                    teams[j].GP += fixtures[i].match;
                    teams[j].GF += fixtures[i].Homescore;
                    teams[j].GA += fixtures[i].Awayscore;
                    teams[j].GD = teams[i].GF - teams[i].GA;

                     if (fixtures[i].Homescore > fixtures[i].Awayscore){
                        teams[j].W += 1;

                }
                     else if (fixtures[i].Homescore < fixtures[i].Awayscore)
                {
                        teams[j].L += 1;
                }
                     else if (fixtures[i].Homescore == fixtures[i].Awayscore){
                           teams[j].D += 1;

                }
                }
        }
    }

     if (fixtures[i].Awayid == 1 )
     {
        for (var j = 0; j <teams.length; j++)
        {
            if (teams[j].id == fixtures[i].Awayid)
                {
                    teams[j].GP += fixtures[i].match;
                    teams[j].GF += fixtures[i].Awayscore;
                    teams[j].GA += fixtures[i].Homescore;
                    teams[j].GD = teams[i].GF - teams[i].GA;

                     if (fixtures[i].Homescore < fixtures[i].Awayscore){
                        teams[j].W += 1;

                }
                     else if (fixtures[i].Homescore > fixtures[i].Awayscore)
                 {
                        teams[j].L += 1;
                }
                     else if (fixtures[i].Homescore == fixtures[i].Awayscore){
                           teams[j].D += 1;

                }
                }
        }
    }

    if (fixtures[i].Homeid == 2)
    {
        for (var j = 0; j <teams.length; j++)
        {
            if (teams[j].id == fixtures[i].Homeid)
                {
                    teams[j].GP += fixtures[i].match;
                    teams[j].GF += fixtures[i].Homescore;
                    teams[j].GA += fixtures[i].Awayscore;
                    teams[j].GD = teams[i].GF - teams[i].GA;

                     if (fixtures[i].Homescore > fixtures[i].Awayscore){
                        teams[j].W += 1;

                }
                     else if (fixtures[i].Homescore < fixtures[i].Awayscore){
                        teams[j].L += 1;
                }
                     else if (fixtures[i].Homescore == fixtures[i].Awayscore){
                           teams[j].D += 1;

                }
                }
        }
    }

     if (fixtures[i].Awayid == 2 )
     {
        for (var j = 0; j <teams.length; j++)
        {
            if (teams[j].id == fixtures[i].Awayid)
                {
                    teams[j].GP += fixtures[i].match;
                    teams[j].GF += fixtures[i].Awayscore;
                    teams[j].GA += fixtures[i].Homescore;
                    teams[j].GD = teams[i].GF - teams[i].GA;

                     if (fixtures[i].Homescore < fixtures[i].Awayscore){
                        teams[j].W += 1;

                }
                     else if (fixtures[i].Homescore > fixtures[i].Awayscore){
                        teams[j].L += 1;
                }
                     else if (fixtures[i].Homescore == fixtures[i].Awayscore){
                           teams[j].D += 1;

                }
                }
        }
    }   

依此类推，直到遍历每个团队

for (var x = 0; x < teams.length; x++)                //Calculates Total 
points for all teams
{
    teams[x].pts = teams[x].W * 3 + teams[x].D;
}

window.onload = function()
{
var tableContainer = document.querySelector("#table");
var table = "";

teams.sort(function(a,b)
{return b.pts - a.pts});

for (var i = 0; i<teams.length; i++)
{
    table += "<tr>" + 
                 "<td>" + teams[i].name + "</td>"+
                 "<td>" + teams[i].GP + "</td>"+
                 "<td>" + teams[i].W + "</td>"+
                 "<td>" + teams[i].D + "</td>"+
                 "<td>" + teams[i].L + "</td>"+
                 "<td>" + teams[i].GF + "</td>"+
                 "<td>" + teams[i].GA + "</td>"+
                 "<td>" + (teams[i].GF - teams[i].GA) + "</td>"+
                 "<td>" + ( (teams[i].W * 3) + teams[i].D) + "</td>"+
            "</tr>";
}
    tableContainer.innerHTML+=table;
};

Answer 1

你在一些地方做类似的事情

teams[j].GD = teams[i].GF - teams[i].GA;

现在， i是fixtures索引，而j是teams索引

因为您有20支球队和21支固定装置，所以当j == 20（第21个索引）时，球队[i]将是未定义的