如果我能得到以下字符串
([{"data":{"id":"1","user_name":"tutor","book":"123","role":"Tutor"}}]);
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我该如何提醒它?data.user_name显示未定义.
$.getJSON('http://mydomain.com/getmyDetail.php?jsoncallback=?', function(data) {
alert(data.user_name);
});
}
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另一个问题,如果我想给URL增加一些价值,比如
,如何直接放入getJSON函数
$.getJSON('http://mydomain.com/getmyDetail.php?username='+username'+'&role='+role+'&'jsoncallback=?' ?
我希望这篇文章不会重复.
我想画一条线,如图所示,可能有不同的线宽和渐变.我尝试过createLinearGradient,但它并不像我预期的那样.我应该使用图像吗?或者我如何渲染上面的线?
我可以和PixiJS合作.
更新:我现在可以使用渐变颜色生成线条但是如何创建动态宽度线条呢?
$(function() {
var canvas = document.getElementById("canvas"),
ctx = canvas.getContext("2d"),
painting = false,
lastX = 0,
lastY = 0;
canvas.onmousedown = function (e) {
if (!painting) {
painting = true;
} else {
painting = false;
}
lastX = e.pageX - this.offsetLeft;
lastY = e.pageY - this.offsetTop;
ctx.lineJoin = ctx.lineCap = 'round';
};
var img = new Image();
img.src = "http://i.imgur.com/K6qXHJm.png";
canvas.onmousemove = function (e) {
if (painting) {
mouseX = e.pageX - this.offsetLeft;
mouseY = e.pageY …Run Code Online (Sandbox Code Playgroud)