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----  如何遍历日志表，生成josn文件内容呢？  (http://foxtable.com/bbs/dispbbs.asp?boardid=2&id=152744)

--  作者：李孝春
--  发布时间：2020/7/20 16:07:00
--  如何遍历日志表，生成josn文件内容呢？
现有一表“日志”有如下字段和内容

此主题相关图片如下：1122.png

Dim jo As New JObject
Dim ja As New JArray
jo("danweiname") = "AAA"
jo("name") = "BB"
jo("date") = ja \'
ja.Add(New JObject) \'给数组添加两个对象成员
ja.Add(New JObject)
ja(0)("time") = "2020-12-11"
ja(0)("context") = "下午"
ja(1)("time") = "2020-12-12"
ja(1)("context") = "中午"
Output.Show(jo.ToString)

上述代码可以固定生成
{
"danweiname": "AAA",
"name": "BB",
"date": [
{
"time": "2020-12-11",
"context": "下午"
},
{
"time": "2020-12-12",
"context": "中午"
}
]
}

随着日志表记录越来越多这个相对固定生成josn的形式就不大方便了

有没有办法实现如下功能呢？
1、根据日志表中的danweiname name time三个字段作为条件分类生成context内容
2、先判断danweiname 如上josn结果先显示单位名称（若遇多个单位：需要先一个单位显示完毕了才生成下一个单位的）
3、判断name，如上josn结果根据单位名称显示name （若遇一个单位，日志记录里有多个name值相同的，先显示完毕了才显示下一个name的相关内容）
4、判断time且满足danweiname name的条件时，如上josn结果根据time先后顺序进行数据生成并显示context的对应值

--  作者：有点蓝
--  发布时间：2020/7/20 16:29:00
--
使用getvalues+select遍历即可

\'定义数组集合的时候，要在类型后加上括号，表示这是一个数组集合。
Dim Arys As List(Of String())
Arys = DataTables("订单").GetValues("danweiname|name") \'列名用符号|分割
\'注意循环变量是字符型数组，所以类型是String()，而不是String
For Each Ary As String() In Arys
    Output.Show(Ary(0) & "|" & Ary(1))
for each dr as datarow in DataTables("订单").select("danweiname= \'" & Ary(0) & "\' and name=xxxx")
Output.Show(dr(“time”))
next
Next

--  作者：李孝春
--  发布时间：2020/7/20 17:05:00
--  回复：（有点蓝）使用getvalues+select遍历即可'定义数...

Dim Arys As List(Of String())
Arys = DataTables("josn").GetValues("danweiname|name") \'列名用符号|分割
\'注意循环变量是字符型数组,所以类型是String(),而不是String
For Each Ary As String() In Arys
Output.Show(Ary(0) & "|" & Ary(1))
Dim jo As New JObject
Dim ja As New JArray
jo("danweiname") = Ary(0)
jo("name") = Ary(1)
jo("date") = ja \'
ja.Add(New JObject) \'给数组添加两个对象成员
ja.Add(New JObject)
For Each dr As DataRow In DataTables("josn").Select("danweiname= \'" & Ary(0) & "\' and name=\'" & Ary(1) & "\'")
Output.Show(dr("tiem"))
Output.Show(dr("context"))
ja(0)("tiem") = dr("tiem")
ja(0)("context") = dr("context")
ja(1)("tiem") = dr("tiem")
ja(1)("context") = dr("context")
Output.Show(jo.ToString)
Next
Next

红色部分启用之后会报错不启用则生成如下：
2012-12-12
下午
{
"danweiname": "AAA",
"name": "BB"
}
2020-11-11
中午
{
"danweiname": "AAA",
"name": "BB"
}
2020-11-11
WANSHANG
{
"danweiname": "AAA",
"name": "BB"
}
2012-11-12
CE
{
"danweiname": "AAA",
"name": "CC"
}
2012-11-13
ZHONGWU
{
"danweiname": "BBB",
"name": "QQ"
}

--  作者：有点蓝
--  发布时间：2020/7/20 17:13:00
--

Dim Arys As List(Of String())
Arys = DataTables("josn").GetValues("danweiname|name") \'列名用符号|分割
\'注意循环变量是字符型数组,所以类型是String(),而不是String
Dim jaaa As New JArray
Dim jo,jo2 As JObject
For Each Ary As String() In Arys
Output.Show(Ary(0) & "|" & Ary(1))
jo = New JObject
jo("danweiname") = Ary(0)
jo("name") = Ary(1)
jo("date") = New JArray\'

For Each dr As DataRow In DataTables("josn").Select("danweiname= \'" & Ary(0) & "\' and name=\'" & Ary(1) & "\'")
Output.Show(dr("tiem"))
Output.Show(dr("context"))
jo2 = New JObject
jo2("tiem") = dr("tiem")
jo2("context") = dr("context")
jo("date").add(jo2)
Next
jaaa.Add(jo)
Next

Output.Show(jaaa.ToString)

[此贴子已经被作者于2020/7/20 17:13:28编辑过]

--  作者：李孝春
--  发布时间：2020/7/20 17:35:00
--  回复：（有点蓝）Dim Arys As List(Of String())Arys ...
再麻烦老师指导下上述代码运行还是没有成功提示如下：
jo("date").add(jo2)
这个提示没有ADD成员我tab查看精灵提示里面只有parse tostring两个

--  作者：有点蓝
--  发布时间：2020/7/21 8:20:00
--

For Each Ary As String() In Arys
Output.Show(Ary(0) & "|" & Ary(1))
jo = New JObject
jo("danweiname") = Ary(0)
jo("name") = Ary(1)
dim ja2 as New JArray\'

For Each dr As DataRow In DataTables("josn").Select("danweiname= \'" & Ary(0) & "\' and name=\'" & Ary(1) & "\'")
Output.Show(dr("tiem"))
Output.Show(dr("context"))
jo2 = New JObject
jo2("tiem") = dr("tiem")
jo2("context") = dr("context")
ja2.add(jo2)
Next
  jo("date") = ja2
jaaa.Add(jo)
Next

--  作者：李孝春
--  发布时间：2020/7/21 9:14:00
--

老师还是有点小问题没有能够成功生成想要的josn 麻烦老师指导下
下载信息  [文件大小：   下载次数： ]
点击浏览该文件:josn测试.foxdb

代码内容
Dim Arys As List(Of String())
Arys = DataTables("josn").GetValues("danweiname|name")
Dim jaaa As New JArray
Dim jo,jo2 As JObject
For Each Ary As String() In Arys
Output.Show(Ary(0) & "|" & Ary(1))
jo = New JObject
jo("danweiname") = Ary(0)
jo("name") = Ary(1)
Dim ja2 As New JArray\'

For Each dr As DataRow In DataTables("josn").Select("danweiname= \'" & Ary(0) & "\' and name=\'" & Ary(1) & "\'")
Output.Show(dr("tiem"))
Output.Show(dr("context"))
jo2 = New JObject
jo2("tiem") = dr("tiem")
jo2("context") = dr("context")
ja2.add(jo2)
Next
jo("date") = ja2
jaaa.Add(jo)
Next

运行提示：

此主题相关图片如下：11111.jpg

[此贴子已经被作者于2020/7/21 9:17:15编辑过]

--  作者：有点蓝
--  发布时间：2020/7/21 9:41:00
--
jo2("tiem") = cstr(dr("tiem"))

--  作者：李孝春
--  发布时间：2020/7/21 17:47:00
--  回复：（有点蓝）jo2("tiem") = cstr(dr("tiem"))
有点蓝老师经过你的指导现在代码如下：
Dim Arys As List(Of String())
Arys = DataTables("josn").GetValues("danweiname|name")
Dim jaaa As New JArray
Dim jo,jo2 As JObject
For Each Ary As String() In Arys
\'Output.Show(Ary(0) & "|" & Ary(1))
jo = New JObject
jo("danweiname") = Ary(0)
jo("name") = Ary(1)
Dim ja2 As New JArray\'
For Each dr As DataRow In DataTables("josn").Select("danweiname= \'" & Ary(0) & "\' and name=\'" & Ary(1) & "\'")
\'Output.Show(dr("tiem"))
\'Output.Show(dr("context"))
jo2 = New JObject
jo2("tiem") = cstr(dr("tiem"))
jo2("context") = cstr(dr("context"))
ja2.add(jo2)
Next
jo("date") = ja2
jaaa.Add(jo)
Next
\'Output.Show(jaaa.ToString)
Dim content As String
content &= jaaa.ToString
\'Output.Show(content)
Dim lj As String = Date.Today & "save.json"
Dim FileName As String = ProjectPath & lj
FileSys.WriteAllText(FileName, content, True)

代码运行后得到的json达到预期，并且成功将json内容写入文件里
[
{
"danweiname": "AAAA",
"name": "BB",
"date": [
{
"tiem": "2020-09-01",
"context": "CES"
},
{
"tiem": "2020-11-11",
"context": "REW"
},
{
"tiem": "2020-12-12",
"context": "TRE"
}
]
},
{
"danweiname": "AAAA",
"name": "QQ",
"date": [
{
"tiem": "2019-12-12",
"context": "UY"
},
{
"tiem": "2020-11-21",
"context": "IUYIU"
}
]
},
{
"danweiname": "BBBB",
"name": "CC",
"date": [
{
"tiem": "2019-03-20",
"context": "RTYE"
},
{
"tiem": "2020-09-03",
"context": "EWR"
}
]
},
{
"danweiname": "CCCC",
"name": "WW",
"date": [
{
"tiem": "2018-09-01",
"context": "TREWR"
},
{
"tiem": "2019-02-01",
"context": "Q"
}
]
},
{
"danweiname": "DDDD",
"name": "EE",
"date": [
{
"tiem": "2020-07-21",
"context": "432W"
}
]
}
]

参照帮助代码如下：
Dim json As String = jaaa.ToString
Dim jojo As JObject = JObject.Parse(json)
Output.Show("单位名称:" & jojo("danweiname"))
Output.Show("姓名:" & jojo("name"))
For Each ep As JToken In jojo("date")
Output.Show( "日期:" & ep("tiem").ToString() & "记录:" & ep("cotext").ToString() )
Next
运行无法正常，提示报错，麻烦看看是不是我将json结构理解有误。

[此贴子已经被作者于2020/7/21 17:48:00编辑过]

--  作者：李孝春
--  发布时间：2020/7/21 18:00:00
--  回复：（有点蓝）jo2("tiem") = cstr(dr("tiem"))
有点蓝老师参照你发布在论坛里的exweui我试一下将所生成的json文件解析成如下页面没有成功麻烦老师指导下谢谢

此主题相关图片如下：11111.jpg
以下内容是专门发给李孝春浏览

内部函数名json
内容：
Dim e As RequestEventArgs = args(0)
Dim wb As New weui
wb.AppendHTML("<link rel=\'stylesheet\' href=\'./weui/exweui.css\'/>",True)
Dim fl As String = HttpServer.WebPath & "\\save.json"
If FileSys.FileExists(fl)
Dim txt As String = FileSys.ReadAllText(fl)
Dim jo As JObject = Jobject.Parse(txt)
\'If jo("danweiname") IsNot Nothing Then
With ExWeUI.WebUI.AddStepGroup("","step1","",,2)
For Each jt As JToken In jo("date")
With .AddStep("st01","",jt("tiem").ToString)
.Description = jt("context").ToString
End With
Next
wb.InsertHTML(.BuildHtml)
End With
\'End If
e.WriteString(wb.Build)
Else
e.WriteString("没有查到信息")
End If

运行后页面提示错误
.NET Framework 版本：4.0.30319.42000
Foxtable 版本：2020.5.29.8
错误所在事件：自定义函数,json
详细错误信息：
调用的目标发生了异常。
Error reading JObject from JsonReader. Current JsonReader item is not an object: StartArray. Path \'\', line 1, position 1.