var len = +second.lenght; //这个加号的作用是什么？，去掉+号也可啊
越努力越幸运！！！
The problem of merging arrays with jquery source code?-PHP Chinese website Q&A-The problem with merging arrays with jquery source code?-PHP Chinese website Q&A
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+second.length中, 若second.length为数字型的字符串, 如"123", 将会被转换为123(number类型), 若为非数字型字符串,将会被转换为NAN.
这是JS中的一种特殊写法!
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The problem of merging arrays with jquery source code?-PHP Chinese website Q&A-The problem with merging arrays with jquery source code?-PHP Chinese website Q&A
Look around and learn.
+second.length中, 若second.length为数字型的字符串, 如"123", 将会被转换为123(number类型), 若为非数字型字符串,将会被转换为NAN.
这是JS中的一种特殊写法!