如何处理在文本框中输入的多个数据类型值以进行搜索

问题描述

下面是Xaml代码，其中有一个组合框，其中包含数据库列名（硬编码）。接下来，有一个文本框，它将在该ComboBox Selected类型值下获取要搜索的值。 Xaml代码

<StackPanel Orientation="Horizontal">
                <Label Content="Search By" Width="100"/>
                <ComboBox Name="CmbSearch" Width="100" ItemsSource="{Binding ColNames}" SelectedValue="{Binding SearchBy}"/>
            </StackPanel>
            <StackPanel Orientation="Horizontal">
                <Label Content="Enter the Value" Width="100"/>
                <TextBox Name="T" Style="{StaticResource Txt}" Text="{Binding Searching,UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}"/>
            </StackPanel>
<DataGrid Name="DG" ItemsSource="{Binding customer}" SelectedItem="{Binding SelectedCustomer}"  AutoGenerateColumns="False" CanUserAddRows="False"
    Height="310" Width="310" Margin="10" HorizontalAlignment="Right" CanUserDeleteRows="True">
                <DataGrid.Columns>
                    <DataGridTextColumn Header="Id" Binding="{Binding Path='Id',UpdateSourceTrigger=PropertyChanged}" IsReadOnly="True"/>
                    <DataGridTextColumn Header="Name" Binding="{Binding Path='Name',UpdateSourceTrigger=PropertyChanged}" IsReadOnly="True" />
                    <DataGridTextColumn Header="Age" Binding="{Binding Path='Age',UpdateSourceTrigger=PropertyChanged}" IsReadOnly="True" />
                    <DataGridTextColumn Header="Country" Binding="{Binding Path='Country',UpdateSourceTrigger=PropertyChanged}" IsReadOnly="True" />
                    <DataGridCheckBoxColumn Header="Active" Binding="{Binding Path='Active',Converter={StaticResource convert}}" IsReadOnly="True"/>
                    <DataGridTemplateColumn Header="Delete Record" IsReadOnly="True">
                        <DataGridTemplateColumn.CellTemplate >
                            <DataTemplate>
                                <Button Command="{Binding DataContext.CmdDeleteUser,RelativeSource={RelativeSource AncestorType={x:Type Window}}}" CommandParameter="{Binding}" Width="60" Margin="2"  Content="Delete" />
                            </DataTemplate>
                        </DataGridTemplateColumn.CellTemplate>
                    </DataGridTemplateColumn>
                </DataGrid.Columns>
            </DataGrid>

viewmodel

private string _SearchBy;

        public string SearchBy  
        {
            get { return _SearchBy; }
            set { _SearchBy = value;
                
               OnPropertyChange("SearchBy"); 
                
                
            }
        }

        private string _Searching;

        public string Searching
        {
            get { return _Searching; }
            set
            {
                _Searching = value;
                OnPropertyChange("Searching");
                if (Searching != null)
                { 
                     collectionView.Filter = new Predicate<Object>(Search);
                    
                }


            }
        }
        private bool Search(Object obj)
        {
            
            Customer cus = (Customer)obj;
            if((SearchBy.Equals("ID")))
            {
                if (cus.Id.Equals(Convert.ToInt32(Searching)))
                {
                    return true;
                }
                else
                {
                    return false;
                }
                
            }
            else if(SearchBy.Equals("Name")) 
            {
                if (cus.Name.Contains(Searching))
                {
                    return true;
                }
                else
                {
                    return false;
                }
            }
            else if(SearchBy.Equals("Age")) 
            {
                if (cus.Age.Equals(Convert.ToInt32(Searching)))
                {
                    return true;
                }
                else
                {
                    return false;
                }
            }
            else if(SearchBy.Equals("Country"))
            {
                if (cus.Country.Contains(Searching))
                {
                    return true;
                }
                else
                {
                    return false;
                }
            }
            else if(SearchBy.Equals("Active"))
            {

                if (cus.Active.Equals(Convert.ToBoolean(Searching)))
                {
                    return true;
                }
                else
                {
                    return false;
                }
            }
            else
            {
                return false;
            }                    
        }

“搜索姓名和国家/地区”工作正常，但Id，Age和Active遇到类型问题。我还为Active（这是一个组合框）创建了一个IValueconverter。对于其他类型我该怎么办？

解决方法

您可以使用int.TryParse方法来尝试解析字符串值，然后调用Equals。

您应该使用switch语句。然后，您的Search方法可以实现如下：

private bool Search(Object obj)
{
    Customer cus = (Customer)obj;
    switch (_SearchBy)
    {
        case "ID":
            return int.TryParse(_Searching,out int id) && cus.Id.Equals(id);
        case "Name":
            return cus.Name.Contains(Searching);
        case "Age":
            return int.TryParse(_Searching,out int age) && cus.Age.Equals(age);
        case "Country":
            return cus.Country.Contains(Searching);
    }

    return false;
}