CJson array 下标访问方法
用下标访问json array 时,第一个元素,也就是下标为0的元素,直接用jsonArraycase[0]的方式是编译不过的,其实源码里做了说明的:
Value &operator[]( UInt index );
/// Access an array element (zero based index )
/// (You may need to say ‘value[0u]’ to get your compiler to distinguish
/// this from the operator[] which takes a string.)
因为运算符[]的参数是无符号型的,对于0而言,由于符号位的差别,有符号0跟无符号0是有区别的,因此要用jsonArraycase[0u]来表示是无符号0;