如何使用两个过滤器过滤数据视图 [英] How to filter a dataview with two filters

问题描述

我有一个包含高尔夫比赛结果的数据视图。我希望根据让分将结果分成三个部分

我有两个全局变量：

 GlobalVariables.DivNo 

和

 GlobalVariables.DivNo2 

从csv文件中定义为16和20

对于第一个分部，我的代码令人满意，是

 Dim LowHandi As String = GlobalVariables.DivNo + 1 
 MResultsDV.RowFilter =Handicap< &安培; LowHandi 

第三个分区代码，也能令人满意地工作，是

 MResultsDV.RowFilter =让分> &安培; GlobalVariables.DivNo2 

但是我的代码需要过滤17到20之间的差点结果不起作用。



什么我试过了：



我的第一次尝试是

 Dim HighHandi As String = GlobalVariables.DivNo2 + 1 
 MResultsDV.RowFilter =让分> &安培; GlobalVariables.DivNo 
 MResultsDV.RowFilter =Handicap< &安培; HighHandi 

然而，最后一个过滤器写了第一个。

所以，我试过

 Dim HighHandi As String = GlobalVariables .DivNo2 + 1 
 MResultsDV.RowFilter =让分> &安培; GlobalVariables.DivNo和Handicap< &安培; HighHandi 

但出现以下错误;

System.InvalidCastException：'从字符串Handicap> 16转换为Long类型无效。'

然后我尝试了

 Dim HighHandi As String = GlobalVariables.DivNo2 + 1 
 MResultsDV.RowFilter =Handicap> &安培; GlobalVariables.DivNo AndAlsoHandicap< &安培; HighHandi 

但是出现了这个错误; System.InvalidCastException：'从字符串Handicap> 16转换为'Boolean'类型无效。'



我也试过

 MResultsDV .RowFilter ='让分> &安培; GlobalVariables.DivNo'和'障碍< &安培;运行但不起作用的HighHandi'

解决方案

这里应该是两个数字之间返回的语法

 MResultsDV.RowFilter =  让分> = & GlobalVariables.DivNo&  &Handicap< =& HighHandi 

A DataView.RowFilter属性（System.Data）| Microsoft Docs [ ^ ]属性的工作方式与 DataColumn.Expression属性（System.Data）| Microsoft Docs [ ^ ]。

因此，您可以构建复杂的表达式，例如：

 DataView11.RowFilter =   ColumnName1 = 555 AND（ColumnName2 like'A *'OR ColumnName3比如'* A'） 

运算符：

允许使用布尔AND，OR和NOT运算符进行连接。您可以使用括号将子句分组并强制优先。 AND运算符优先于其他运算符。例如：



（LastName ='Smith'或LastName ='Jones'）AND FirstName ='John'

字符串运算符：

要连接字符串，请使用+字符。 DataSet类的CaseSensitive属性的值确定字符串比较是否区分大小写。

请按照我提供的链接。

I have a dataview containing the results of a golf competition. I wish to split the results into three divisions based on "Handicap"
I have two Global Variables namely:

GlobalVariables.DivNo

and

GlobalVariables.DivNo2

which are defined from a csv file as 16 and 20
For the first Division my code, which works satisfactorily, is

Dim LowHandi As String = GlobalVariables.DivNo + 1
        MResultsDV.RowFilter = "Handicap <" & LowHandi

the third Division code, which also works satisfactorily, is

MResultsDV.RowFilter = "Handicap >" & GlobalVariables.DivNo2

However my code which needs to filter out the results for handicaps between 17 and 20 does not work.

What I have tried:

My first try was

Dim HighHandi As String = GlobalVariables.DivNo2 + 1
        MResultsDV.RowFilter = "Handicap >" & GlobalVariables.DivNo
        MResultsDV.RowFilter = "Handicap <" & HighHandi

However, the last filter over wrote the first.
So, I tried

Dim HighHandi As String = GlobalVariables.DivNo2 + 1
        MResultsDV.RowFilter = "Handicap >" & GlobalVariables.DivNo And "Handicap <" & HighHandi

but got the following error;
System.InvalidCastException: 'Conversion from string "Handicap >16" to type 'Long' is not valid.'
I then tried

Dim HighHandi As String = GlobalVariables.DivNo2 + 1
        MResultsDV.RowFilter = "Handicap >" & GlobalVariables.DivNo AndAlso "Handicap <" & HighHandi

but got this error; System.InvalidCastException: 'Conversion from string "Handicap >16" to type 'Boolean' is not valid.'

I also tried

MResultsDV.RowFilter = '"Handicap >" & GlobalVariables.DivNo' And '"Handicap <" & HighHandi'

which ran but did not work

解决方案

Here should be the syntax to return in between two numbers

MResultsDV.RowFilter = "Handicap >=" & GlobalVariables.DivNo & " AND Handicap <=" & HighHandi

A DataView.RowFilter Property (System.Data) | Microsoft Docs[^] property works in the same manner as DataColumn.Expression Property (System.Data) | Microsoft Docs[^].
So, you can build complex expression, for example:

DataView11.RowFilter = "ColumnName1 = 555 AND (ColumnName2 Like 'A*' OR ColumnName3 Like '*A')"

Operators:

Concatenation is allowed using Boolean AND, OR, and NOT operators. You can use parentheses to group clauses and force precedence. The AND operator has precedence over other operators. For example:

(LastName = 'Smith' OR LastName = 'Jones') AND FirstName = 'John'

String operators:

To concatenate a string, use the + character. The value of the CaseSensitive property of the DataSet class determines whether string comparisons are case-sensitive.

Please, follow the links i've provided.

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