js与jQuery实现获取table中的数据并拼成json字符串操作示例

function tabToJSON(id) {
    var trs = document.getElementById(id).getElementsByTagName("tr");//获得tr数组
    var titles = trs[0].getElementsByTagName("td");  //获得表头td数组
    var json = "";
    for(var i = 1; i < trs.length; i++) {
      var tds = trs[i].getElementsByTagName("td");  
      json += "{"; 
      //拼装json
      for(var j = 0; j < tds.length; j++) 
        json += titles[j].innerHTML + ":" + tds[j].innerHTML + ",";
      json = json.substring(0, json.length - 1) + "},";
    }
    json = "[" + json.substring(0, json.length - 1) + "]";
    document.getElementById("test").innerHTML = json;
}

function tabToJSONForJquery(id) {
    var titles = $("#" + id).find("tr:first td");  //获得表头td数组
    //遍历非表头的，tr、td...拼装json
    var json = "[" + $("#" + id).find("tr:not(:first)").map(function(i, e) {
      return "{" + $(e).children("td").map(function(j, el) {
        return $(titles[j]).html() + ":" + $(el).html();
      }).get().join(",") + "}";
    }).get().join(",") + "]";
    $("#test").html(json);
}

<script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>

<table id="tbl" border="1">
<tr><td>编号</td><td>年龄</td><td>单元</td><td>房间号</td></tr>
<tr><td>1</td><td>25</td><td>1</td><td>1-2</td></tr>
<tr><td>2</td><td>22</td><td>1</td><td>1-1</td></tr>
<tr><td>3</td><td>21</td><td>3</td><td>3-3</td></tr>
<tr><td>4</td><td>20</td><td>2</td><td>2-2</td></tr>
<tr><td>5</td><td>35</td><td>4</td><td>4-2</td></tr>
</table>
<div id="test"></div>