根据某些条件更改网格视图值答案

【问题标题】：Change Grid view value based on some condition根据某些条件更改网格视图值
【发布时间】：2019-10-24 16:28:48
【问题描述】：

我有一个网格视图控件，其中包含从用户填写的表单填充的几列。在表单中，某些值不是强制性的，如果用户不选择它们，则显示为“选择”在网格视图中。当我加载网格视图时，如何将该值更改为“无”之类的相对值。换句话说，如果该列包含“选择”，则将其更改为“无”

这是我用来填充Gridview的代码

Private Sub LoadGridAll()

    txtSearchEmployee.Text = ""
    Try
        Using conn As New SqlConnection(ConfigurationManager.ConnectionStrings("XXX").ConnectionString)

            Using cmd As New SqlCommand("SELECT EmployeeCodes.Code, EmployeeCodes.FirstName , EmployeeCodes.LastName , EmployeeCodes.EmployeeID , CostCentre , ExaminationType.ExaminationTypeName  , PhysicalExam.PhysicalExamName , ExaminationType.ExaminationTypeName  , PhysicalExam.PhysicalExamName , Audiogram.AudiogramName , AudiogramRec.AudiogramRecName,LungFunction.LungFunctionName,ChestResults,ECGResult,DrugScreeningResult,BloodGlucoseResult,GGTResult,LeftEyeDayNight,RightEyeDayNight,LeftEyeCorrDayNight,RightEyeCorrDayNight,VisualFieldLeftDayNight,VisualFieldRightDayNight,ColourVisionDayNight,DeptPerceptionDayNight,OptometristYesNo,Outcome.Name , OutcomeRecommendations.OutcomeRecommendationsName,OtherProblems,Notes,DateTested,NextDueDate FROM  MedicalResults,EmployeeCodes,ExaminationType,PhysicalExam,Audiogram,AudiogramRec,LungFunction,Outcome,OutcomeRecommendations WHERE MedicalResults.EmployeeID = EmployeeCodes.EmployeeID AND ExaminationType.ExaminationTypeID = MedicalResults.ExaminationTypeID AND PhysicalExam.PhysicalExamID = MedicalResults.PhysicalExamType AND Audiogram.AudiogramID = MedicalResults.AudiogramID AND MedicalResults.AudiogramRecID = AudiogramRec.AudiogramRecID AND LungFunction.LungFunctionID = MedicalResults.LungFunctionID AND OutcomeRecommendations.OutcomeRecommendationsID = MedicalResults.OutcomeRecommendationsID AND Outcome.OutcomeID = MedicalResults.OutcomeID ", conn)

                conn.Open()

                Dim sda As New SqlDataAdapter(cmd)
                Dim dt As New DataTable()
                sda.Fill(dt)

                For Each row As DataRow In dt.Rows
                    Dim strDetail As Object
                    strDetail = row.Item(10)

                    If strDetail = "Select" Then

                        strDetail = "None"

                    End If
                Next row

                GridViewAll.DataSource = dt
                GridViewAll.DataBind()                   


                conn.Close()

            End Using

        End Using

    Catch ex As Exception

    End Try

End Sub

【问题讨论】：

标签： asp.net vb.net gridview

【解决方案1】：

首先，我不会将“Select”保存到 DB，保存空值 (DBNull.Value) 会更有意义。然后在您的选择语句中，您可以使用函数 IsNull(yourField,'None')。编辑：如果网格中有 Null 值，也可以使用 DataGridView 的属性：

Me.GridViewAll.RowsDefaultCellStyle.NullValue = "None"

然而，如果你想像你展示的那样做，你已经很接近了——你只需要将新的 String 值保存到 DataTable：

row.Item(10) = "None" 'strDetail

【讨论】：