點評：主要功能實現翻開的2張牌如果配對就會消除，否則2張牌都會返回背面，下面為大家介紹一下需求分析及示例代碼，感興趣的朋友可以學習下
翻開的2張牌如果配對就會消除，否則2張牌都會返回背面。
需求分析
怎麼繪製正的牌面和背的牌面及配對成功後怎麼消除牌面
怎么生成牌組並且確定每張牌的位置和對應的圖片
怎麼洗牌
怎麼記錄牌組的配對信息
怎麼確定點擊事件是第一次點擊還是第二次點擊
作弊事件的處理：兩次點擊同一張牌點擊已經消除的牌麵點擊牌面之外的區域
牌翻開之後需要給一定時間讓玩家看清楚，怎麼實現暫停
鼠標點擊事件的響應及獲得鼠標點擊位置的坐標從而確定點擊的是哪一張牌
MYCode:
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta charset="utf-8" />
<title>test </title>
<script type="text/javascript">
var ctx;
var canvas;
var card;
var first_pick = true; //第一次點擊的標誌
var first_card = -1;
var second_card;
var back_color = "rgb(255,0,0)"; //卡片背面顏色
var table_color = "#FFF";
var deck = []; //note
var first_x = 10;
var first_y = 50;
var margin = 30;
var card_width = 50;
var card_height = 50;
var pairs = [
["1_a.jpg", "1_b.jpg"],
["2_a.jpg", "2_b.jpg"],
["3_a.jpg", "3_b.jpg"],
["4_a.jpg", "4_b.jpg"],
["5_a.jpg", "5_b.jpg"]
];
function draw_back()//繪製卡片背面
{
ctx.fillStyle = back_color;
ctx.fillRect(this.sx, this.sy, this.swidth, this.sheight);
}
function Card(sx, sy, swidth, sheight, img, info)//構造函數
{
this.sx = sx;
this.sy = sy;
this.swidth = swidth;
this.sheight = sheight;
this.info = info;
this.img = img;
this.draw = draw_back;
}
function make_deck()//生成卡組並繪製
{
var i;
var a_card;
var b_card;
var a_pic;
var b_pic;
var cx = first_x;
var cy = first_y;
for (i = 0; i < pairs.length; i++)
{
a_pic = new Image();
a_pic.src = pairs[i][0];
a_card = new Card(cx, cy, card_width, card_height, a_pic, i);
deck.push(a_card);
b_pic = new Image();
b_pic.src = pairs[i][1];
b_card = new Card(cx, cy + card_height + margin, card_width, card_height, b_pic, i);
deck.push(b_card);
cx = cx + card_width + margin; //note
a_card.draw();
b_card.draw();
}
}
function shuffle()//洗牌
{
var i;
var j;
var temp_info;
var temp_img;
var deck_length = deck.length;
var k;
for (k = 0; k < 3 * deck_length; k++)
{
i = Math.floor(Math.random() * deck_length);
j = Math.floor(Math.random() * deck_length);
temp_info = deck[i].info;
temp_img = deck[i].img;
deck[i].info = deck[j].info;
deck[i].img = deck[j].img;
deck[j].info = temp_info;
deck[j].img = temp_img;
}
}
function choose(ev)
{
//var out;
var mx;
var my;
//var pick1;
//var pick2;
var i;
//note
if (ev.layerX || ev.layerX == 0) { // Firefox
mx = ev.layerX;
my = ev.layerY;
} else if (ev.offsetX || ev.offsetX == 0) { // Opera
mx = ev.offsetX;
my = ev.offsetY;
}
for (i = 0; i < deck.length; i++)
{
card = deck[i];
if (card.sx >= 0)//牌未被消除
{
//判斷點擊的是哪一張牌
if (mx > card.sx && mx < card.sx + card.swidth && my > card.sy && my < card.sy + card.sheight)
{
if (i != first_card)//如果兩次點擊同一張牌不做處理
break;
}
}
}
if (i < deck.length)
{
if (first_pick)//如果是第一次點擊
{
first_card = i;
first_pick = false; //note
ctx.drawImage(card.img, card.sx, card.sy, card.swidth, card.sheight);
}
else
{
first_pick = true; //note
second_card = i;
ctx.drawImage(card.img, card.sx, card.sy, card.swidth, card.sheight);
tid=setTimeout(flip_back,1000);
}
}
}
function flip_back()
{
if (card.info == deck[first_card].info)//配對成功
{
ctx.fillStyle = table_color;
ctx.fillRect(deck[first_card].sx, deck[first_card].sy, deck[first_card].swidth, deck[first_card].sheight);
ctx.fillRect(deck[second_card].sx, deck[second_card].sy, deck[second_card].swidth, deck[second_card].sheight);
deck[first_card].sx = -1;
deck[second_card].sy = -1;
first_card=-1;
}
else
{
deck[first_card].draw();
deck[second_card].draw();
first_card=-1;
}
}
function init()
{
canvas = document.getElementById('canvas');
canvas.addEventListener('click', choose, false);
ctx = canvas.getContext('2d');
make_deck();
shuffle();
}
</script>
</head>
<body>
<canvas/>
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</body>
</html>