[BUG] Fix bug: nil pointer was accessed when getting value in a empty assoc array. [BUG] Fix bug: when first member was added, -1 would be returned faultily [BUG] 修复 bug: 从空关联数组中获取数据时，访问了空指针 [BUG] 修复 bug: 添加第一个成员时，返回 -1
[BUG] Fix bug: nil pointer was accessed when getting value in a empty assoc array.
[BUG] Fix bug: when first member was added, -1 would be returned faultily
[BUG] 修复 bug: 从空关联数组中获取数据时，访问了空指针
[BUG] 修复 bug: 添加第一个成员时，返回 -1

Andrew-M-C/cAssocArray,Andrew-M-C/cAssocArray