我有两个组合框和xml文件，我想从xml填充组合框1中的服务器名称，并根据服务器名称填充第二个组合框
本文关键字：组合 xml 服务器 填充 第二个 文件 两个 | 更新日期: 2023-09-27 18:21:39
XML：
<?xml version="1.0" encoding="utf-8"?>
<servers>
<server>s2
<database>db1</database>
<database>db2</database>
</server>
<server>s3
<database>db3</database>
<database>db4</database>
</server>
</servers>
我想获得基于服务器名称的数据库&以字符串类型列表的形式返回。
视图：
该函数将从第一个组合框中获取服务器名称作为参数，并基于该参数过滤数据库并填充第二个组合框
public List<string> GetDatabases(string serv)
{
var item = from items in xdoc.Descendants("database")
where (string)items.Element("server") == serv
select items.Elements("database").ToList();
foreach (var items in item)
{
lstDBName.Add(items.ToString());
}
return lstDBName;
}
您发布的XML无效。如果你用XML验证器测试它，你会发现它给出了以下错误：
Errors in the XML document:
1: 1 Content is not allowed in prolog.
您可以通过添加一个属性来存储服务器名称来轻松修复它，如下所示：
<?xml version="1.0" encoding="utf-8"?>
<servers>
<server name="s2">
<database>db1</database>
<database>db2</database>
</server>
<server name="s3">
<database>db3</database>
<database>db4</database>
</server>
</servers>
你可以这样修改（并简化一点）你的代码：
public List<string> GetDatabases(string serv)
{
XDocument xdoc = XDocument.Load("XMLFile1.xml");
var lstDBName = (from items in xdoc.Descendants("server")
where items.Attribute("name").Value == serv
from item in items.Elements("database")
select item.Value)
.ToList();
return lstDBName;
}
我从一个名为XMLFile1.XML的文件中读取了该方法中的XML，您可以通过读取XML的方式更改该位。
此代码示例将返回一个包含两个字符串的列表，其中值为"db1"answers"db2"，如预期的
正如我所理解的，你需要一些机制，在第一个组合中进行选择时，会用第一个组合的相关数据更新第二个组合（基于你的问题名称：
我有两个组合框和xml文件，我想从xml填充组合框1中的服务器名称，并根据服务器名称填充第二个组合框
)。
这是一个基于两个可观察集合及其更新机制的解决方案。1.Xaml编码：
<Window x:Class="SimpleDataGrid.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:simpleDataGrid="clr-namespace:SimpleDataGrid"
Title="MainWindow" Height="350" Width="525">
<Window.DataContext>
<simpleDataGrid:GridViewModel/>
</Window.DataContext>
<Grid >
<DataGrid x:Name="SelectDataGrid" ItemsSource="{Binding Persons}" HorizontalAlignment="Left" VerticalAlignment="Top" AutoGenerateColumns="False">
<DataGrid.Columns>
<DataGridCheckBoxColumn x:Name="dgCheckBox" Header="Select" Width="45" Binding="{Binding IsChecked}"/>
<DataGridTextColumn Header="FIRST NAME" Width="125" Binding="{Binding FNAME}"/>
<DataGridTextColumn Header="LAST NAME" Width="125" Binding="{Binding LNAME}"/>
<DataGridComboBoxColumn Header="Servers"
DisplayMemberPath="ServerName" SelectedValueBinding="{Binding SelectedServer, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}">
<DataGridComboBoxColumn.ElementStyle>
<Style TargetType="ComboBox">
<Setter Property="ItemsSource" Value="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type DataGridCell}}, Path=DataContext.Servers}"/>
<Setter Property="IsReadOnly" Value="True"/>
</Style>
</DataGridComboBoxColumn.ElementStyle>
<DataGridComboBoxColumn.EditingElementStyle>
<Style TargetType="ComboBox">
<Setter Property="ItemsSource" Value="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type DataGridCell}}, Path=DataContext.Servers}"/>
</Style>
</DataGridComboBoxColumn.EditingElementStyle>
</DataGridComboBoxColumn>
<DataGridComboBoxColumn Header="Dbs"
DisplayMemberPath="DbName"
SelectedValueBinding="{Binding SelectedDb, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}">
<DataGridComboBoxColumn.ElementStyle>
<Style TargetType="ComboBox">
<Setter Property="ItemsSource" Value="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type DataGridCell}}, Path=DataContext.Dbs}"/>
<Setter Property="IsReadOnly" Value="True"/>
</Style>
</DataGridComboBoxColumn.ElementStyle>
<DataGridComboBoxColumn.EditingElementStyle>
<Style TargetType="ComboBox">
<Setter Property="ItemsSource" Value="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type DataGridCell}}, Path=DataContext.Dbs}"/>
</Style>
</DataGridComboBoxColumn.EditingElementStyle>
</DataGridComboBoxColumn>
</DataGrid.Columns>
</DataGrid>
</Grid></Window>
2.给出解决方案的主模型代码。UpdateDbCollection方法可以调用您的GetDatabases方法，查询与服务器相关的数据库，将该数据放在"newDbs"列表中，并在添加新数据和远程处理旧数据时使用新数据更新第二个组合可观察集合。
public class Person : BaseObservableObject
{
private string _lName;
private string _fName;
private bool _checked;
private object _selectedServer;
private DbDetails _selectedDb;
public Person()
{
Dbs = new ObservableCollection<DbDetails>();
Servers = new ObservableCollection<ServerDetails>(new List<ServerDetails>
{
new ServerDetails
{
ServerName = "A",
DbDetailses = new List<DbDetails>
{
new DbDetails{DbName = "AA"},
new DbDetails{DbName = "AB"},
new DbDetails{DbName = "AC"},
}
},
new ServerDetails
{
ServerName = "B",
DbDetailses = new List<DbDetails>
{
new DbDetails{DbName = "BA"},
new DbDetails{DbName = "BB"},
new DbDetails{DbName = "BC"},
}
},
new ServerDetails
{
ServerName = "C",
DbDetailses = new List<DbDetails>
{
new DbDetails{DbName = "CA"},
new DbDetails{DbName = "CB"},
}
}
});
}
public DbDetails SelectedDb
{
get { return _selectedDb; }
set
{
_selectedDb = value;
OnPropertyChanged();
}
}
public object SelectedServer
{
get { return _selectedServer; }
set
{
_selectedServer = value;
OnPropertyChanged();
UpdateDbCollection(SelectedServer as ServerDetails);
}
}
private void UpdateDbCollection(ServerDetails serverDetails)
{
//here you can get your db details by selected server
var newDbs = serverDetails.DbDetailses;
newDbs.ForEach(details => Dbs.Add(details));
var valuesToClear =
Dbs.Where(
existingDbDetails => newDbs.FirstOrDefault(dbDetails => existingDbDetails == dbDetails) == null).ToList();
valuesToClear.ForEach(details => Dbs.Remove(details));
}
public ObservableCollection<ServerDetails> Servers { get; set; }
public ObservableCollection<DbDetails> Dbs { get; set; }
public bool IsChecked
{
get { return _checked; }
set
{
_checked = value;
OnPropertyChanged();
}
}
public string LNAME
{
get { return _lName; }
set
{
_lName = value;
OnPropertyChanged();
}
}
public string FNAME
{
get { return _fName; }
set
{
_fName = value;
OnPropertyChanged();
}
}
}
3.型号：
public class ServerDetails:BaseObservableObject
{
private string _serverName;
public string ServerName
{
get { return _serverName; }
set
{
_serverName = value;
OnPropertyChanged();
}
}
public List<DbDetails> DbDetailses { get; set; }
}
public class DbDetails:BaseObservableObject
{
private string _dbName;
public string DbName
{
get { return _dbName; }
set
{
_dbName = value;
OnPropertyChanged();
}
}
}
查看型号代码：
公共类GridViewModel:BaseObservableObject｛
public GridViewModel() { var l = new List<Person> { new Person {FNAME = "John", LNAME = "W"}, new Person {FNAME = "George", LNAME = "R"}, new Person {FNAME = "Jimmy", LNAME = "B"}, new Person {FNAME = "Marry", LNAME = "B"}, new Person {FNAME = "Ayalot", LNAME = "A"}, }; Persons = new ObservableCollection<Person>(l); } public ObservableCollection<Person> Persons { get; set; }}
BaseObservableObject是INotifyPropertyChanged的一个简单实现。
我希望它能帮助你。感谢问候，