小编Thi*_*rte的帖子

当我不使用分页时,一切正常(我在这个集合中只有3条记录,因此所有这些都列在这里):

db.suppliers.find({location: {$near: [-23.5968323, -46.6782386]}},{name:1,badge:1}).sort({badge:-1})
{ "_id" : ObjectId("4f33ff549112b9b84f000070"), "badge" : 3, "name" : "Dedetizadora Alvorada" }
{ "_id" : ObjectId("4f33ff019112b9b84f00005b"), "badge" : 2, "name" : "Sampex Desentupidora e Dedetizadora" }
{ "_id" : ObjectId("4f33feae9112b9b84f000046"), "badge" : 1, "name" : "Higitec Desentupimento e Dedetização" }

但是当我尝试从第一页到第二页分页时,一条记录没有显示,一条记录重复:

db.suppliers.find({location: {$near: [-23.5968323, -46.6782386]}},{name:1,badge:1}).sort({badge:-1}).skip(0).limit(2)
{ "_id" : ObjectId("4f33ff549112b9b84f000070"), "badge" : 3, "name" : "Dedetizadora Alvorada" }
{ "_id" : ObjectId("4f33feae9112b9b84f000046"), "badge" : 1, "name" : "Higitec Desentupimento e Dedetização" }

db.suppliers.find({location: {$near: [-23.5968323, -46.6782386]}},{name:1,badge:1}).sort({badge:-1}).skip(2).limit(2) …

我正在正确读取并打印“ mousePos”标题中的鼠标坐标，但是当我在画布上绘制时，使用相同的精确坐标，通过单击和拖动，我画的是最底端和最右边。我可以通过不使用style.canvas.width =“ 512px”来解决此问题，但是我无法设置大小。大小必须为512 x 512。

有小费吗？

    
        var resize =1;
        var mouseX, mouseY;
        var pen = "?";
        var canvas = document.getElementById('canvas');
        var menu = document.getElementById('menu');
        var ctx = canvas.getContext('2d');
        var fill = "#FF0000";  //Red
    
        canvas.style.width="512px";
        canvas.style.height="512px";
    
        menu.style.width="512";
        menu.style.height="512";
    
        canvas.addEventListener("mousedown", penDown);
        canvas.addEventListener("mouseup", penUp);
    
        function mouseMove(event) {
            mouseX = event.clientX - ctx.canvas.offsetLeft;
            mouseY = event.clientY - ctx.canvas.offsetTop;
            document.getElementById('mousePos').innerHTML = "Mouse Position: X" + mouseX + " Y" + mouseY;
    
            if(pen == "down") {
                ctx.fillRect(mouseX, mouseY, 4, 4);
            }
        }
    
        function penDown() { …