C# c wpf绑定组合框到SQL Server数据库
我试图将我的数据库绑定到combobox项目combobox,但似乎无法使其正常工作。我试着在XAML中传递它,以及后端代码,但Combobox总是空的。任何帮助都将不胜感激 SQL Server本地数据库:数据库1 数据来源:数据集1;表:项目表 组合框名称:ProjectComboBox 以下是我的XAML代码:C# c wpf绑定组合框到SQL Server数据库,c#,sql-server,wpf,combobox,dataset,C#,Sql Server,Wpf,Combobox,Dataset,我试图将我的数据库绑定到combobox项目combobox,但似乎无法使其正常工作。我试着在XAML中传递它,以及后端代码,但Combobox总是空的。任何帮助都将不胜感激 SQL Server本地数据库:数据库1 数据来源:数据集1;表:项目表 组合框名称:ProjectComboBox 以下是我的XAML代码: <Window x:Class="WpfApplication1.MainWindow" xmlns="http://schemas.microsoft.com/wi
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WpfApplication1"
mc:Ignorable="d"
Title="MainWindow" Height="500" Width="850">
<Grid>
<ComboBox x:Name="ProjectComboBox"
ItemsSource="{Binding Path=ProjectTable}"
DisplayMemberPath="ProjectName"
SelectedValuePath="RFIDirectory"
HorizontalAlignment="Left"
VerticalAlignment="Top"
Width="297" Height="26"
SelectionChanged="comboBox_SelectionChanged">
</ComboBox>
}
不能直接绑定到SQL Server表记录。但是,可以绑定到表示表记录的对象列表。
正如@Paul Abbott提到的,一旦表单加载,您必须首先初始化组合框项。或者一种丑陋的方法是添加一个虚拟记录,一旦选择它,将引发selection changed事件,然后执行代码。
不要为您的连接打开和sql数据适配器执行单独的try-catch块。这是多余的
在sql连接上使用using语句可在连接后正确关闭和处置
public MainWindow()
{
InitializeComponent();
UpdateItems(); // Maybe initialize here?
}
private void comboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
ProjectComboBox.Items.Clear(); // Remove this. AFAIK, the selected item will be cleared.
UpdateItems();
}
private void UpdateItems()
{
try
{
using(SqlConnection con = new SqlConnection("Data Source=(local);Initial Catalog=Database1;Integrated Security=True"))
{
con.Open();
SqlDataAdapter ProjectTableTableAdapter = new SqlDataAdapter("SELECT * FROM PROJECTNAME", con);
DataSet1 ds = new DataSet1();
ProjectTableTableAdapter.Fill(ds, "t");
ProjectComboBox.ItemsSource = ds.Tables["t"].DefaultView;
ProjectComboBox.DisplayMemberPath = "ProjectName";
ProjectComboBox.SelectedValuePath = "RFIDirectory";
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
<ComboBox x:Name="ProjectComboBox"
ItemsSource="{Binding Path=ProjectTable}" // Not sure of what the impact will be by adding this because you have already defined the item source on your code-behind. I'd prefer you remove this and use XAML binding when you're following a design pattern like MVVM or MVPVM.
DisplayMemberPath="ProjectName"
SelectedValuePath="RFIDirectory"
HorizontalAlignment="Left"
VerticalAlignment="Top"
Width="297" Height="26"
SelectionChanged="comboBox_SelectionChanged">
</ComboBox>
您正在comboBox_SelectionChanged中填充组合框,该组合框将永远不会触发,因为组合框为空,因此无法更改为任何内容。我希望在初始化Component;之后缺少一个};。
public MainWindow()
{
InitializeComponent();
UpdateItems(); // Maybe initialize here?
}
private void comboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
ProjectComboBox.Items.Clear(); // Remove this. AFAIK, the selected item will be cleared.
UpdateItems();
}
private void UpdateItems()
{
try
{
using(SqlConnection con = new SqlConnection("Data Source=(local);Initial Catalog=Database1;Integrated Security=True"))
{
con.Open();
SqlDataAdapter ProjectTableTableAdapter = new SqlDataAdapter("SELECT * FROM PROJECTNAME", con);
DataSet1 ds = new DataSet1();
ProjectTableTableAdapter.Fill(ds, "t");
ProjectComboBox.ItemsSource = ds.Tables["t"].DefaultView;
ProjectComboBox.DisplayMemberPath = "ProjectName";
ProjectComboBox.SelectedValuePath = "RFIDirectory";
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
<ComboBox x:Name="ProjectComboBox"
ItemsSource="{Binding Path=ProjectTable}" // Not sure of what the impact will be by adding this because you have already defined the item source on your code-behind. I'd prefer you remove this and use XAML binding when you're following a design pattern like MVVM or MVPVM.
DisplayMemberPath="ProjectName"
SelectedValuePath="RFIDirectory"
HorizontalAlignment="Left"
VerticalAlignment="Top"
Width="297" Height="26"
SelectionChanged="comboBox_SelectionChanged">
</ComboBox>