本文的示例演示了如何運(yùn)用CustomFieldValueCells事件找到一個(gè)特定的行/列標(biāo)頭，這個(gè)行/列標(biāo)頭是根據(jù)其列/行的匯總值確定的。本例中查找只包含列匯總值為零的。本例中的列標(biāo)頭是通過(guò)事件參數(shù)的FindCell方法添加的，然后再通過(guò) Remove 的方法對(duì)其刪除。

示例代碼如下：

C#

using System;
using System.Globalization;
using System.Windows.Forms;
using DevExpress.XtraPivotGrid;

namespace XtraPivotGrid_FindCells {
    public partial class Form1 : Form {
        public Form1() {
            InitializeComponent();
            pivotGridControl1.CustomFieldValueCells += 
                new PivotCustomFieldValueCellsEventHandler(pivotGrid_CustomFieldValueCells);
        }
        void Form1_Load(object sender, EventArgs e) {
            PivotHelper.FillPivot(pivotGridControl1);
            pivotGridControl1.DataSource = PivotHelper.GetDataTable();
            pivotGridControl1.BestFit();
        }

        // Handles the CustomFieldValueCells event to remove columns with
        // zero summary values.
        protected void pivotGrid_CustomFieldValueCells(object sender,
                             PivotCustomFieldValueCellsEventArgs e) {
            if (pivotGridControl1.DataSource == null) return;
            if (radioGroup1.SelectedIndex == 0) return;

            // Obtains the first encountered column header whose column
            // matches the specified condition, represented by a predicate.
            FieldValueCell cell = e.FindCell(true, new Predicate<object[]>(

                // Defines the predicate returning true for columns
                // that contain only zero summary values.
                delegate(object[] dataCellValues) {
                    foreach (object value in dataCellValues) {
                        if (!object.Equals((decimal)0, value))
                            return false;
                    }
                    return true;
            }));

            // If any column header matches the condition, this column is removed.
            if (cell != null) e.Remove(cell);
        }
        void pivotGridControl1_FieldValueDisplayText(object sender, 
                                        PivotFieldDisplayTextEventArgs e) {
            if(e.Field == pivotGridControl1.Fields[PivotHelper.Month]) {
                e.DisplayText = CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName((int)e.Value);
            }
        }
        void radioGroup1_SelectedIndexChanged(object sender, EventArgs e) {
            this.pivotGridControl1.LayoutChanged();
            pivotGridControl1.BestFit();
        }        
    }
}

VB

Imports Microsoft.VisualBasic
Imports System
Imports System.Globalization
Imports System.Windows.Forms
Imports DevExpress.XtraPivotGrid

Namespace XtraPivotGrid_FindCells
    Partial Public Class Form1
        Inherits Form
        Public Sub New()
            InitializeComponent()
            AddHandler pivotGridControl1.CustomFieldValueCells, _
                AddressOf pivotGrid_CustomFieldValueCells
        End Sub
        Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
            PivotHelper.FillPivot(pivotGridControl1)
            pivotGridControl1.DataSource = PivotHelper.GetDataTable()
            pivotGridControl1.BestFit()
        End Sub

        ' Handles the CustomFieldValueCells event to remove columns with
        ' zero summary values.
        Protected Sub pivotGrid_CustomFieldValueCells(ByVal sender As Object, _
                                                      ByVal e As PivotCustomFieldValueCellsEventArgs)
            If pivotGridControl1.DataSource Is Nothing Then
                Return
            End If
            If radioGroup1.SelectedIndex = 0 Then
                Return
            End If

            ' Obtains the first encountered column header whose column
            ' matches the specified condition, represented by a predicate.
            Dim cell As FieldValueCell = _
                e.FindCell(True, New Predicate(Of Object())(AddressOf AnonymousMethod1))

            ' If any column header matches the condition, this column is removed.
            If cell IsNot Nothing Then
                e.Remove(cell)
            End If
        End Sub
        
        ' Defines the predicate returning true for columns
        ' that contain only zero summary values.
        Private Function AnonymousMethod1(ByVal dataCellValues() As Object) As Boolean
            For Each value As Object In dataCellValues
                If (Not Object.Equals(CDec(0), value)) Then
                    Return False
                End If
            Next value
            Return True
        End Function
        Private Sub pivotGridControl1_FieldValueDisplayText(ByVal sender As Object, _
                                                       ByVal e As PivotFieldDisplayTextEventArgs) _
                                                       Handles pivotGridControl1.FieldValueDisplayText
            If Object.Equals(e.Field, pivotGridControl1.Fields(PivotHelper.Month)) Then
                e.DisplayText = _
                    CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName(CInt(Fix(e.Value)))
            End If
        End Sub
        Private Sub radioGroup1_SelectedIndexChanged(ByVal sender As Object, _
                                                     ByVal e As EventArgs) _
                                                     Handles radioGroup1.SelectedIndexChanged
            Me.pivotGridControl1.LayoutChanged()
            pivotGridControl1.BestFit()
        End Sub
    End Class
End Namespace