如何访问使用javascript的对象数组中的对象的属性？

下面是一个Ajax调用的responseText的一个元素：如何访问使用javascript的对象数组中的对象的属性？

[{ 
    "hitcount": { 
     "0": "3351" 
    }, 
    "page": { 
     "0": "1" 
    }, 
    "title": { 
     "0": "Hypoxia upregulates Rab11-family interacting protein 4 through HIF-1\u03b1 to promote the metastasis of hepatocellular carcinoma." 
    }, 
    "authorString": { 
     "0": "Hu F, Deng X, Yang X, Jin H, Gu D, Lv X, Wang C, Zhang Y, Huo X, Shen Q, Luo Q, Zhao F, Ge T, Zhao F, Chu W, Shu H, Yao M, Fan J, Qin W." 
    }, 
    "pubYear": { 
     "0": "2015" 
    }, 
    "journalVolume": "", 
    "issue": "", 
    "pageInfo": "", 
    "pmid": { 
     "0": "25745995" 
    }, 
    "abstract_": { 
     "0": "Hypoxic microenvironment is a powerful driving force for the invasion and metastasis of hepatocellular carcinoma (HCC). Hypoxia-inducible factor 1\u03b1 (HIF-1\u03b1), as a crucial regulator of transcriptional responses to hypoxia, induces the expression of multiple target genes involved in different steps of HCC metastatic process. It is critical to find target genes associated with metastasis under hypoxia for shedding new light on molecular mechanism of HCC metastasis. In this study, we uncovered that hypoxia could induce the upregulation of Rab11-family interacting protein 4 (Rab11-FIP4) and activation of Rab11-FIP4 promoter by HIF-1\u03b1. The overexpression of Rab11-FIP4 significantly enhanced the mobility and invasiveness of HCC cells in vitro, also contributed to distant lung metastasis in vivo, whereas silencing of Rab11-FIP4 decreased the ability of migration and invasion in HCC cells in vitro and suppressed lung metastasis in vivo. Rab11-FIP4 facilitated HCC metastasis through the phosphorylation of PRAS40, which was regulated by mTOR. Furthermore, the expression level of Rab11-FIP4 was significantly increased in HCC tissues and high expression of Rab11-FIP4 was closely correlated with vascular invasion and poor prognosis in HCC patients. A markedly positive correlation between the expression of Rab11-FIP4 and HIF-1\u03b1 was observed in HCC tissues and combination of Rab11-FIP4 and HIF-1\u03b1 was a more valuable predictor of poor prognosis for HCC patients. In conclusion, Rab11-FIP4 is a target gene of HIF-1\u03b1 and has a pro-metastatic role in HCC, suggesting that Rab11-FIP4 may be a promising candidate target for HCC treatment.Oncogene advance online publication, 9 March 2015; doi:10.1038\/onc.2015.49." 
    }, 
    "journalTitle": { 
     "0": "Oncogene" 
    }, 
    "pdfURL": "", 
    "arrayOfPersons": [{ 
     "firstname": "dean", 
     "lastname": "wood", 
     "avatar_path": null, 
     "username": "deanwood" 
    }, { 
     "firstname": "dean", 
     "lastname": "wood", 
     "avatar_path": null, 
     "username": "deanwood" 
    }, { 
     "firstname": "Anne", 
     "lastname": "Smith", 
     "avatar_path": null, 
     "username": "annesmith" 
    }] 
}]

我的字符串转换为JavaScript对象：

var json_obj = JSON.parse(xmlhttp.responseText);

我试图访问对象数组的属性从这个元素（位于元素的末尾），但没有成功。我试过以下没有成功：

json_obj[i].arrayOfPersons[i].firstname;

请问可以somone提醒吗？

来源

2015-07-13 dave

这是无效的JSON的开始。你确定这正是XHR出现的内容吗？ –

在两个位置使用相同的“i”是没有意义的。一般来说，你看起来不错，你只需确保你正在访问正确的元素。 –

你用'json_obj [0] .arrayOfPersons [i] .firstname;'试过了吗？ – Timo

获取arrayOfPersons的最后一个人：

var json = '[{"hitcount":{"0":"3351"},"page":{"0":"1"},"title":{"0":"Hypoxia upregulates Rab11-family interacting protein 4 through HIF-1\u03b1 to promote the metastasis of hepatocellular carcinoma."},"authorString":{"0":"Hu F, Deng X, Yang X, Jin H, Gu D, Lv X, Wang C, Zhang Y, Huo X, Shen Q, Luo Q, Zhao F, Ge T, Zhao F, Chu W, Shu H, Yao M, Fan J, Qin W."},"pubYear":{"0":"2015"},"journalVolume":"","issue":"","pageInfo":"","pmid":{"0":"25745995"},"abstract_":{"0":"Hypoxic microenvironment is a powerful driving force for the invasion and metastasis of hepatocellular carcinoma (HCC). Hypoxia-inducible factor 1\u03b1 (HIF-1\u03b1), as a crucial regulator of transcriptional responses to hypoxia, induces the expression of multiple target genes involved in different steps of HCC metastatic process. It is critical to find target genes associated with metastasis under hypoxia for shedding new light on molecular mechanism of HCC metastasis. In this study, we uncovered that hypoxia could induce the upregulation of Rab11-family interacting protein 4 (Rab11-FIP4) and activation of Rab11-FIP4 promoter by HIF-1\u03b1. The overexpression of Rab11-FIP4 significantly enhanced the mobility and invasiveness of HCC cells in vitro, also contributed to distant lung metastasis in vivo, whereas silencing of Rab11-FIP4 decreased the ability of migration and invasion in HCC cells in vitro and suppressed lung metastasis in vivo. Rab11-FIP4 facilitated HCC metastasis through the phosphorylation of PRAS40, which was regulated by mTOR. Furthermore, the expression level of Rab11-FIP4 was significantly increased in HCC tissues and high expression of Rab11-FIP4 was closely correlated with vascular invasion and poor prognosis in HCC patients. A markedly positive correlation between the expression of Rab11-FIP4 and HIF-1\u03b1 was observed in HCC tissues and combination of Rab11-FIP4 and HIF-1\u03b1 was a more valuable predictor of poor prognosis for HCC patients. In conclusion, Rab11-FIP4 is a target gene of HIF-1\u03b1 and has a pro-metastatic role in HCC, suggesting that Rab11-FIP4 may be a promising candidate target for HCC treatment.Oncogene advance online publication, 9 March 2015; doi:10.1038\/onc.2015.49."},"journalTitle":{"0":"Oncogene"},"pdfURL":"","arrayOfPersons":[{"firstname":"dean","lastname":"wood","avatar_path":null,"username":"deanwood"},{"firstname":"dean","lastname":"wood","avatar_path":null,"username":"deanwood"},{"firstname":"Anne","lastname":"Smith","avatar_path":null,"username":"annesmith"}]}]'; 
 

 
function show() { 
 
    var json_obj = JSON.parse(json); 
 
    result = document.getElementById("result"); 
 
    lastPerson = json_obj[0].arrayOfPersons[json_obj[0].arrayOfPersons.length - 1]; 
 
    result.innerHTML = lastPerson.firstname + " " +lastPerson.lastname; 
 
}

Last person of arrayOfPersons: 
 
<div id="result"></div> 
 
<button onclick="show();">Show</button>

来源

2015-07-13 12:30:42 Christoph

首先：解决你的JSON，它在最后缺少一个]。除此之外，你可能想遍历所有可能的firstNames。试试这个：

for (var i = 0; i < json_obj.length; i++) { 
    for (var j = 0; j < json_obj[i].arrayOfPersons.length; j++) { 
     var result = json_obj[i].arrayOfPersons[j]; 
     console.log(result.firstname); 
    } 
}

来源

2015-07-13 12:27:39 Dodekeract

如果xmlhttp.responseText返回值的类型是JSON，你并不需要解析它。你可以这样使用：

var json_obj = xmlhttp.responseText; 
json_obj[i].arrayOfPersons[i].firstname

来源

2015-07-13 12:32:04 Gaslan

如何访问使用javascript的对象数组中的对象的属性？

回答

相关问题