Question

我想将数组传递给函数并对其进行处理，但我担心会发生错误，说board_pt未定义。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;
}

board是已定义的全局数组

Answer 1

问题是board_pt只有1项，而js在这种情况下知道board_pt是对象：

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，那么它不太可能有一个名为number的属性。你的意思是length？

Answer 3

根据您的评论，您必须将 previous_boardPoint 定义为数组。要在javascript中声明数组，您需要在代码中使用 - var previous_boardPoint = [];。还要定义每个元素（如果有的话），如previous_boardPoint[0] = val1; previous_boarPoint[1] = val2;等等。

如果您的代码中没有这些内容，那么在所有可能的情况下，您将在函数 set_boardPoint 中将 board_pt 定义为未定义。

javascript函数参数

3 个答案: