Question

如何设置ComBox的默认值，即绑定Combox的数据源？

有一个Combox1，现在我要把它设置成包含如下三种值：MRB，UAI, Scrap，供用户选择，且如何获得用户选择的结果的值。

Answer 1

Xaml文件里：

<ComboBox  ItemsSource="{Binding DisplayItems,Mode=TwoWay}"

                  SelectedItem="{Binding SelectedDisplayItem,Mode=TwoWay}"/>

        <Label  Content="{Binding SelectedDisplayItem, Mode=TwoWay}"/>   

cs文件里：

 public partial class MainWindow : Window, INotifyPropertyChanged

    {

        public event PropertyChangedEventHandler PropertyChanged;

        public MainWindow()

        {

            InitializeComponent();

            this.DataContext = this;

            List<string> items = new List<string>();

            items.Add("MRB");

            items.Add("UAI");

            items.Add("Scrap");

            DisplayItems = items;

        }

        private List<string> _displayItems;

        public List<string> DisplayItems

        {

            get { return _displayItems; }

            set

            {

                _displayItems = value;

                NotifyPropertyChanged("DisplayItems");

            }

        }

        private string _selectedDisplayItem;

        public string SelectedDisplayItem

        {

            get { return _selectedDisplayItem; }

            set 

            { 

                _selectedDisplayItem = value;

                NotifyPropertyChanged("SelectedDisplayItem");

            }

        }

        private void NotifyPropertyChanged(String info)

        {

            if (PropertyChanged != null)

            {

                PropertyChanged(this, new PropertyChangedEventArgs(info));

            }

        }

    }

Answer 2

this.cmbuserType.DataSource = ds.Tables[0];
this.cmbuserType.ValueMember = ds.Tables[0].Columns[0].ColumnName.ToString();
this.cmbuserType.DisplayMember = ds.Tables[0].Columns[1].ColumnName.ToString();
加上：
comboBox.SelectedValue="默认值"; //默认值是属于this.cmbuserType.ValueMember里的值。

Answer 3

var str:String='<data>'+
'<items LineId="38" LineName="穗港线" />'+
'<items LineId="39" LineName="穗港线" />'+
'<items LineId="40" LineName="阿萨德" />'+
'<items LineId="58" LineName="qq" />'+
'<items LineId="60" LineName="AAAA" />'+
'<items LineId="66" LineName="111" />'+
'<items LineId="67" LineName="11" />'+
'<items LineId="68" LineName="1234" />'+
'<items LineId="70" LineName="1234eee" />'+
'</data>';
var xml:XML=new XML(str);
var nameArrC:ArrayCollection=new ArrayCollection();
var objOne:Object=new Object();
objOne.id="-1";
objOne.name="所有线路";
nameArrC.addItem(objOne);
for each(var x:XML in xml.items){
var objs:Object=new Object();
objs.id=x.@LineId;
objs.name=x.@LineName;
nameArrC.addItem(objs);
}
paln.lineName.dataProvider=nameArrC;
paln.lineName.labelField="name";
paln.lineName.selectedIndex=0;
lineId="-1";
获取结果可以是这样的：paln.lineName.selectedItem.name;