MVC中Json的使用：Controller中Json的处理

一、当查询得到的数据符合前台要求，不需要做任何处理，直接DataList To Json 返回前台。

代码：

1  var allEntities = service.QueryByPage(this.GetSearchFilter(searchModel), "InsertedDateUtc  Descending", pageSize, searchModel.PageIndex + 1, out recordCount);
2  return Json(allEntities, JsonRequestBehavior.AllowGet);

前台得到的Json数据（两条记录）

[
    {
        "DocumentID": "61d09198-198e-403e-89a0-01b98402c8ca",
        "DocumentFileName": "189017.docx.pdf",
        "ContentType": "doc",
        "Size": 167228,
        "InsertedDateUtc": "/Date(1358762613167)/",
        "LastModifiedOnDataSource": "/Date(1358504490000)/",
        "UniqueIDOnDataSource": "189017",
        "IsActive": true,
        "HasBeenIndexed": true,
        "TradeProductID": "1e04dc4d-5a68-4982-ba88-170a3f6525f5",
        "HasProcessedForAlerts": false,
        "Congress": "ESMO-2012",
        "Authors": "Zi Ming Zhao",
        "CongressType": "Poster",
        "DocumentTitle": "立普妥-一级预防中的应用                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        ",
        "EntityState": 2,
        "EntityKey": {
            "EntitySetName": "Document",
            "EntityContainerName": "MVCExampleEntities",
            "EntityKeyValues": [
                {
                    "Key": "DocumentID",
                    "Value": "61d09198-198e-403e-89a0-01b98402c8ca"
                }
            ],
            "IsTemporary": false
        }
    },
    {
        "DocumentID": "a71ea30c-b544-41fa-b008-77adcf7a0250",
        "DocumentFileName": "189153.docx.pdf",
        "ContentType": "doc",
        "Size": 136195,
        "InsertedDateUtc": "/Date(1358762610573)/",
        "LastModifiedOnDataSource": "/Date(1358778247000)/",
        "UniqueIDOnDataSource": "189153",
        "IsActive": true,
        "HasBeenIndexed": true,
        "TradeProductID": "1e04dc4d-5a68-4982-ba88-170a3f6525f5",
        "HasProcessedForAlerts": false,
        "Congress": null,
        "Authors": null,
        "CongressType": null,
        "DocumentTitle": "立普妥-碾碎服用                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            ",
        "EntityState": 2,
        "EntityKey": {
            "EntitySetName": "Document",
            "EntityContainerName": "MVCExampleEntities",
            "EntityKeyValues": [
                {
                    "Key": "DocumentID",
                    "Value": "a71ea30c-b544-41fa-b008-77adcf7a0250"
                }
            ],
            "IsTemporary": false
        }
    }
]

二、当得到的数据不能满足前台需求，比如，我希望加入一个键值对存入总记录数，以方便做分页。

 

   两种方法：

       1、拼字符串，注意return 的是Content( ).

代码

var allEntities = service.QueryByPage(this.GetSearchFilter(searchModel), "InsertedDateUtc  Descending", pageSize, searchModel.PageIndex + 1, out recordCount);
          
           string json = JsonConvert.SerializeObject(allEntities);
           StringBuilder sb = new StringBuilder();
           sb.Append("{");
           sb.Append(""total"");
           sb.Append(":280,");
           sb.Append(""rows"");
           sb.Append(":");
           sb.Append(json);
           sb.Append("}");
  return Content(sb.ToString());
 
          或者直接用String:   string jsonString = "{'total':280,'rows':" + json + "}";  （此方法用easyui测试时，前台无法解析）。
           return Content(jsonString);

前台得到的Json数据

{
    "total": 280,
    "rows": [
        {
            "$id": "1",
            "DocumentID": "61d09198-198e-403e-89a0-01b98402c8ca",
            "DocumentFileName": "189017.docx.pdf",
            "ContentType": "doc",
            "Size": 167228,
            "InsertedDateUtc": "2013-01-21T18:03:33.167",
            "LastModifiedOnDataSource": "2013-01-18T18:21:30",
            "UniqueIDOnDataSource": "189017",
            "IsActive": true,
            "HasBeenIndexed": true,
            "TradeProductID": "1e04dc4d-5a68-4982-ba88-170a3f6525f5",
            "HasProcessedForAlerts": false,
            "Congress": "ESMO-2012",
            "Authors": "Zi Ming Zhao",
            "CongressType": "Poster",
            "DocumentTitle": "立普妥-一级预防中的应用 ",
            "EntityKey": {
                "$id": "2",
                "EntitySetName": "Document",
                "EntityContainerName": "MVCExampleEntities",
                "EntityKeyValues": [
                    {
                        "Key": "DocumentID",
                        "Type": "System.Guid",
                        "Value": "61d09198-198e-403e-89a0-01b98402c8ca"
                    }
                ]
            }
        },
        {
            "$id": "3",
            "DocumentID": "a71ea30c-b544-41fa-b008-77adcf7a0250",
            "DocumentFileName": "189153.docx.pdf",
            "ContentType": "doc",
            "Size": 136195,
            "InsertedDateUtc": "2013-01-21T18:03:30.573",
            "LastModifiedOnDataSource": "2013-01-21T22:24:07",
            "UniqueIDOnDataSource": "189153",
            "IsActive": true,
            "HasBeenIndexed": true,
            "TradeProductID": "1e04dc4d-5a68-4982-ba88-170a3f6525f5",
            "HasProcessedForAlerts": false,
            "Congress": null,
            "Authors": null,
            "CongressType": null,
            "DocumentTitle": "立普妥-碾碎服用 ",
            "EntityKey": {
                "$id": "4",
                "EntitySetName": "Document",
                "EntityContainerName": "MVCExampleEntities",
                "EntityKeyValues": [
                    {
                        "Key": "DocumentID",
                        "Type": "System.Guid",
                        "Value": "a71ea30c-b544-41fa-b008-77adcf7a0250"
                    }

 2、重新创建一个新Json对象，把数据装进去。然后返回前台。

var allEntities = service.QueryByPage(this.GetSearchFilter(searchModel), "InsertedDateUtc  Descending", pageSize, searchModel.PageIndex + 1, out recordCount);
   // 创建JsonResult对象。
           JsonResult j = new JsonResult()
           {
               Data = new
               {
                   total = recordCount,
                   rows = allEntities
               }
           };
           //以下两个参数可选，前台接收有问题时可加上试试
           // j.ContentType = "application/json";     
           //j.ContentEncoding = System.Text.Encoding.UTF8;
           //以下参数设置是否允许GET请求
           j.JsonRequestBehavior = JsonRequestBehavior.AllowGet;
           return j; //此处不能再用 return Json(j, JsonRequestBehavior.AllowGet);//方式，否则相当于把Json又转换了一遍Json，前台接收的数据如下（我用easyui测试时，前台无法解析）。

EasyUi环境下有问题的Json

{
    "ContentEncoding": null,
    "ContentType": null,
    "Data": {
        "total": 920,
        "rows": [
            {
                "DocumentID": "61d09198-198e-403e-89a0-01b98402c8ca",
                "DocumentFileName": "189017.docx.pdf",
                "ContentType": "doc",
                "Size": 167228,
                "InsertedDateUtc": "/Date(1358762613167)/",
                "LastModifiedOnDataSource": "/Date(1358504490000)/",
                "UniqueIDOnDataSource": "189017",
                "IsActive": true,
                "HasBeenIndexed": true,
                "TradeProductID": "1e04dc4d-5a68-4982-ba88-170a3f6525f5",
                "HasProcessedForAlerts": false,
                "Congress": "ESMO-2012",
                "Authors": "Zi Ming Zhao",
                "CongressType": "Poster",
                "DocumentTitle": "立普妥-一级预防中的应用                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        ",
                "EntityState": 2,
                "EntityKey": {
                    "EntitySetName": "Document",
                    "EntityContainerName": "MVCExampleEntities",
                    "EntityKeyValues": [
                        {
                            "Key": "DocumentID",
                            "Value": "61d09198-198e-403e-89a0-01b98402c8ca"
                        }
                    ],
                    "IsTemporary": false
                }
            },
            {
                "DocumentID": "a71ea30c-b544-41fa-b008-77adcf7a0250",
                "DocumentFileName": "189153.docx.pdf",
                "ContentType": "doc",
                "Size": 136195,
                "InsertedDateUtc": "/Date(1358762610573)/",
                "LastModifiedOnDataSource": "/Date(1358778247000)/",
                "UniqueIDOnDataSource": "189153",
                "IsActive": true,
                "HasBeenIndexed": true,
                "TradeProductID": "1e04dc4d-5a68-4982-ba88-170a3f6525f5",
                "HasProcessedForAlerts": false,
                "Congress": null,
                "Authors": null,
                "CongressType": null,
                "DocumentTitle": "立普妥-碾碎服用                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            ",
                "EntityState": 2,
                "EntityKey": {
                    "EntitySetName": "Document",
                    "EntityContainerName": "MVCExampleEntities",
                    "EntityKeyValues": [
                        {
                            "Key": "DocumentID",
                            "Value": "a71ea30c-b544-41fa-b008-77adcf7a0250"
                        }
                    ],
                    "IsTemporary": false
                }
            }
        ]
    },
    "JsonRequestBehavior": 0,
    "MaxJsonLength": null,
    "RecursionLimit": null
}

三 、最后一个Json数据查看工具，很方便。
JSON Viewer