循環結果中未定義的對象

Question

我在下面有我的代碼，我注意到當我在html中顯示它時，我在索引0中得到一個[object Object]結果，該結果實際上應該給我153826-00 。
奇怪的是在console.log ，我得到了想要的結果。
有人可以告訴我發生了什么嗎？

 var db = {"Root":{"DataPage":[{"Record":{"PPS_NUM":"3207987 ","PO_NUM":"153826-00 ","OB_TYPE":"SOLK","SHIPMENT":"S258028 "}},{"Record":{"PPS_NUM":"3207500 ","PO_NUM":"10086398 ","OB_TYPE":"SOLK","SHIPMENT":"S257877 "}},{"Record":{"PPS_NUM":"3207562 ","PO_NUM":"","OB_TYPE":"XFLK","SHIPMENT":"S257881X "}},{"Record":{"PPS_NUM":"3198033 ","PO_NUM":"SAMPLES 6-14-17 ","OB_TYPE":"SOLK","SHIPMENT":"S255956 "}},{"Record":{"PPS_NUM":"3207443 ","PO_NUM":"491754-2279 ","OB_TYPE":"SOLK","SHIPMENT":"S257873 "}},{"Record":{"PPS_NUM":"3204961 ","PO_NUM":"","OB_TYPE":"XFLK","SHIPMENT":"S257368 "}},{"Record":{"PPS_NUM":"3207635 ","PO_NUM":"","OB_TYPE":"XFLK","SHIPMENT":"S257904 "}},{"Record":{"PPS_NUM":"3205331 ","PO_NUM":"0188502 ","OB_TYPE":"SOLK","SHIPMENT":"S257450 "}}]}}; var p = db.Root.DataPage; for (var key in p) { if (p.hasOwnProperty(key)) { db+='<p>'+p[key].Record.PO_NUM+'</p>'; $('#display').html(db); console.log(p[key].Record.PO_NUM); } } $('#display').html(db); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <p id="display"></p> 

Answer 1

那是因為您已經將db定義為第一個數組，所以當您+ =時，只需添加數據即可。 只需更改您的第二個數據庫進行輸出即可。

 var db = {"Root":{"DataPage":[{"Record":{"PPS_NUM":"3207987 ","PO_NUM":"153826-00 ","OB_TYPE":"SOLK","SHIPMENT":"S258028 "}},{"Record":{"PPS_NUM":"3207500 ","PO_NUM":"10086398 ","OB_TYPE":"SOLK","SHIPMENT":"S257877 "}},{"Record":{"PPS_NUM":"3207562 ","PO_NUM":"","OB_TYPE":"XFLK","SHIPMENT":"S257881X "}},{"Record":{"PPS_NUM":"3198033 ","PO_NUM":"SAMPLES 6-14-17 ","OB_TYPE":"SOLK","SHIPMENT":"S255956 "}},{"Record":{"PPS_NUM":"3207443 ","PO_NUM":"491754-2279 ","OB_TYPE":"SOLK","SHIPMENT":"S257873 "}},{"Record":{"PPS_NUM":"3204961 ","PO_NUM":"","OB_TYPE":"XFLK","SHIPMENT":"S257368 "}},{"Record":{"PPS_NUM":"3207635 ","PO_NUM":"","OB_TYPE":"XFLK","SHIPMENT":"S257904 "}},{"Record":{"PPS_NUM":"3205331 ","PO_NUM":"0188502 ","OB_TYPE":"SOLK","SHIPMENT":"S257450 "}}]}}; var p = db.Root.DataPage; var output = ""; for (var key in p) { if (p.hasOwnProperty(key)) { output+='<p>'+p[key].Record.PO_NUM+'</p>'; $('#display').html(output); console.log(p[key].Record.PO_NUM); } } $('#display').html(output); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <p id="display"></p> 

Answer 2

db變量是一個對象，將字符串附加到此變量后，它將轉換為字符串，並得到[object Object] 。
只需更改您的變量名

 var db = {"Root":{"DataPage":[{"Record":{"PPS_NUM":"3207987 ","PO_NUM":"153826-00 ","OB_TYPE":"SOLK","SHIPMENT":"S258028 "}},{"Record":{"PPS_NUM":"3207500 ","PO_NUM":"10086398 ","OB_TYPE":"SOLK","SHIPMENT":"S257877 "}},{"Record":{"PPS_NUM":"3207562 ","PO_NUM":"","OB_TYPE":"XFLK","SHIPMENT":"S257881X "}},{"Record":{"PPS_NUM":"3198033 ","PO_NUM":"SAMPLES 6-14-17 ","OB_TYPE":"SOLK","SHIPMENT":"S255956 "}},{"Record":{"PPS_NUM":"3207443 ","PO_NUM":"491754-2279 ","OB_TYPE":"SOLK","SHIPMENT":"S257873 "}},{"Record":{"PPS_NUM":"3204961 ","PO_NUM":"","OB_TYPE":"XFLK","SHIPMENT":"S257368 "}},{"Record":{"PPS_NUM":"3207635 ","PO_NUM":"","OB_TYPE":"XFLK","SHIPMENT":"S257904 "}},{"Record":{"PPS_NUM":"3205331 ","PO_NUM":"0188502 ","OB_TYPE":"SOLK","SHIPMENT":"S257450 "}}]}}; var p = db.Root.DataPage; var htmlValue = ""; for (var key in p) { if (p.hasOwnProperty(key)) { htmlValue +='<p>'+p[key].Record.PO_NUM+'</p>'; $('#display').html(htmlValue); console.log(p[key].Record.PO_NUM); } } $('#display').html(htmlValue); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <p id="display"></p> 

Answer 3

您需要將變量初始化為空字符串。 它考慮將其視為數組，並帶有+號，並將其添加到數組中。 因此，您將獲得[object Object]

 var db = { "Root": { "DataPage": [{ "Record": { "PPS_NUM": "3207987 ", "PO_NUM": "153826-00 ", "OB_TYPE": "SOLK", "SHIPMENT": "S258028 " } }, { "Record": { "PPS_NUM": "3207500 ", "PO_NUM": "10086398 ", "OB_TYPE": "SOLK", "SHIPMENT": "S257877 " } }, { "Record": { "PPS_NUM": "3207562 ", "PO_NUM": "", "OB_TYPE": "XFLK", "SHIPMENT": "S257881X " } }, { "Record": { "PPS_NUM": "3198033 ", "PO_NUM": "SAMPLES 6-14-17 ", "OB_TYPE": "SOLK", "SHIPMENT": "S255956 " } }, { "Record": { "PPS_NUM": "3207443 ", "PO_NUM": "491754-2279 ", "OB_TYPE": "SOLK", "SHIPMENT": "S257873 " } }, { "Record": { "PPS_NUM": "3204961 ", "PO_NUM": "", "OB_TYPE": "XFLK", "SHIPMENT": "S257368 " } }, { "Record": { "PPS_NUM": "3207635 ", "PO_NUM": "", "OB_TYPE": "XFLK", "SHIPMENT": "S257904 " } }, { "Record": { "PPS_NUM": "3205331 ", "PO_NUM": "0188502 ", "OB_TYPE": "SOLK", "SHIPMENT": "S257450 " } }] } }; var p = db.Root.DataPage; var htmlToAppend = ''; for (var key in p) { if (p.hasOwnProperty(key)) { htmlToAppend += '<p>' + p[key].Record.PO_NUM + '</p>'; console.log(p[key].Record.PO_NUM); } } $('#display').html(htmlToAppend); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <p id="display"></p>