课程
/前端开发
/Html5
/Canvas玩转图像处理
代码一样的结果显示不出来是什么问题？？？
2016-08-03
源自：Canvas玩转图像处理 2-3
正在回答
是的，$p的值为“PI1”，只有这样后面的判断才是常量PI1是否已经定义，没有双引号$p的值就是3.14了，而不是常量PI1,这样后面判断的就是3.14了
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感觉不像呀，你与下面的分号比较，它都没有向左的小尾巴，你把下面的复制过去，试试，你的代码没错，那个符号我改了试试，换成冒号，恰好出现你这种情况。
闹够了没有_ 提问者
写的是分号
你那个image.onload里面的drawImage函数后面的符号错了，不是冒号
举报
canvas系列第三课，学会编写图像算法，一起玩转图像处理吧
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