javascript函数参数

Question

我想将一个数组传递给一个函数并对其进行处理，但是我担心，发生错误会说board_pt是未定义的。问题是什么？这是代码：

function set_boardPoint(board_pt,turn) 
{ 
    var no = board_pt.number-1; 
    board[no].row = board_pt.row; 
    board[no].col = board_pt.col; 
    board[no].x = board_pt.x; 
    board[no].y = board_pt.y; 
    board[no].value = turn; 
    board[no].number = board_pt.number; 
} 

板是已经定义

Answer 1

问题一个全局数组是board_pt仅具有1个项目，并且在这些情况下的js知道board_pt作为对象：

function set_boardPoint(board_pt,turn) 
{ 
    var no = board_pt.number-1; 
    if(board[no] != undefined) 
    { 
    board[no].row = board_pt.row; 
    board[no].col = board_pt.col; 
    board[no].x = board_pt.x; 
    board[no].y = board_pt.y; 
    board[no].value = turn; 
    board[no].number = board_pt.number; 
}else 
{ 
board.row = board_pt.row; 
    board.col = board_pt.col; 
    board.x = board_pt.x; 
    board.y = board_pt.y; 
    board.value = turn; 
    board.number = board_pt.number; 
} 
} 

Answer 2

如果board_pt是一个真正的数组，那么它不太可能具有名为number的属性。你的意思是length？

Answer 3

从您的意见，你必须定义previous_boardPoint作为一个数组。要在JavaScript中声明数组，您需要在代码中有 - var previous_boardPoint = [];。也有定义的每个元素（如果您有任何），如previous_boardPoint[0] = val1; previous_boarPoint[1] = val2;等

如果这些东西是不是在你的代码，然后在所有可能的机会，你会得到board_pt为未定义在函数set_boardPoint。