GridLookUpEdit的知识库是RepositoryItemGridLookUpEdit，切确的说GridLookUpEdit只是RepositoryItemGridLookUpEdit的一个壳而已，
这也就是在GridControl的GridView中，对列绑定的是RepositoryItemGridLookUpEdit而不是GridLookUpEdit的原因，RepositoryItemGridLookUpEdit才是GridLookUpEdit的核心，所以处理这个过滤操作，其实就是对RepositoryItemGridLookUpEdit进行操作，
方法的参数也是RepositoryItemGridLookUpEdit类型，这样在GridView中使用RepositoryItemGridLookUpEdit也可以直接调用。eg:
SetGridLookUpEditMoreColumnFilter(gridLookUpEdit1.Properties);
SetGridLookUpEditMoreColumnFilter(repositoryItemGridLookUpEdit1);
/// <summary>
/// 设置GridLookUpEdit多列过滤
/// </summary>
/// <param name="repGLUEdit">GridLookUpEdit的知识库，eg:gridlookUpEdit.Properties</param>
void SetGridLookUpEditMoreColumnFilter(DevExpress.XtraEditors.Repository.RepositoryItemGridLookUpEdit repGLUEdit)
{
repGLUEdit.EditValueChanging += (sender, e) =>
{
this.BeginInvoke(new System.Windows.Forms.MethodInvoker(() => {
GridLookUpEdit edit = sender as GridLookUpEdit;
DevExpress.XtraGrid.Views.Grid.GridView view = edit.Properties.View as DevExpress.XtraGrid.Views.Grid.GridView;
//获取GriView私有变量
System.Reflection.FieldInfo extraFilter = view.GetType().GetField("extraFilter",System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance); List<DevExpress.Data.Filtering.CriteriaOperator> columnsOperators = new List<DevExpress.Data.Filtering.CriteriaOperator>();
foreach (GridColumn col in view.VisibleColumns)
{
if (col.Visible && col.ColumnType == typeof(string))
columnsOperators.Add(new DevExpress.Data.Filtering.FunctionOperator(DevExpress.Data.Filtering.FunctionOperatorType.Contains,
new DevExpress.Data.Filtering.OperandProperty(col.FieldName),
new DevExpress.Data.Filtering.OperandValue(edit.Text)));
} string filterCondition = new DevExpress.Data.Filtering.GroupOperator(DevExpress.Data.Filtering.GroupOperatorType.Or, columnsOperators).ToString(); extraFilter.SetValue(view, filterCondition);
//获取GriView中处理列过滤的私有方法
System.Reflection.MethodInfo ApplyColumnsFilterEx = view.GetType().GetMethod("ApplyColumnsFilterEx", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
ApplyColumnsFilterEx.Invoke(view, null);
})); }; }