救命用的

<Grid x:Name="LayoutRoot" Background="White">
        <Grid.RowDefinitions>
            <RowDefinition Height="*"></RowDefinition>
            <RowDefinition Height="40"></RowDefinition>
            <RowDefinition Height="40"></RowDefinition>
            <RowDefinition Height="40"></RowDefinition>
            <RowDefinition Height="*"></RowDefinition>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*"></ColumnDefinition>
            <ColumnDefinition Width="100"></ColumnDefinition>
            <ColumnDefinition Width="100"></ColumnDefinition>
            <ColumnDefinition Width="*"></ColumnDefinition>
        </Grid.ColumnDefinitions>
        <TextBlock Text="用户名:" Grid.Row="1" Grid.Column="1" Margin="8" Height="30" Width="80" FontSize="20" HorizontalAlignment="Center" FontWeight="Bold" FontFamily="Arial"/>
        <TextBlock Text="密   码:" Grid.Row="2" Grid.Column="1" Margin="8" Height="30" Width="80" FontSize="20" HorizontalAlignment="Center" FontWeight="Bold" FontFamily="Arial"/>
        <TextBox Name="tb_username" Grid.Row="1" Grid.Column="2" Margin="6" Height="28" Width="85" FontSize="20" HorizontalAlignment="Center"  FontFamily="Arial"/>
        <TextBox Name="password" Grid.Row="2" Grid.Column="2" Margin="6" Height="28" Width="85" FontSize="20" HorizontalAlignment="Center"  FontFamily="Arial"/>
        <Button Content="登录" Name="Btn_Login" Grid.Row="3" Grid.Column="1" Margin="8" Height="28" Width="80" FontSize="15" HorizontalAlignment="Center"  FontFamily="Arial" Click="btn_Login_"/>
        <Button Content="注册" Name="Btn_Regin" Grid.Row="3" Grid.Column="2" Margin="8" Height="28" Width="80" FontSize="15" HorizontalAlignment="Center"  FontFamily="Arial" />
    </Grid>

 <!--定义上下两行-->
        <Grid.RowDefinitions>
            <RowDefinition Height="100"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>
        <Grid Grid.Row="0" Background="Beige"/>
        <!--设置标题在第一行-->
        <TextBlock Grid.Row="0" Text="再  现  丝  绸  之  路" HorizontalAlignment="Center" Margin="10" TextAlignment="Center" FontFamily="黑体"
			FontWeight="Black" Foreground="Bisque" FontSize="37" FontStretch="ExtraCondensed"/>
        <!--把第二行分为两列，添加按钮-->
        <Grid Grid.Row="1" Margin="0,5,0,-5" Background="#FF2492D1">

            <Grid.ColumnDefinitions >
                <ColumnDefinition Width="100"/>
                <ColumnDefinition Width="*"/>
            </Grid.ColumnDefinitions>
            <esri:Map Name="MyMap" Grid.Column="1" Background="White" WrapAround="True">
                <esri:ArcGISDynamicMapServiceLayer Url="http://localhost/ArcGIS/rest/services/sczl/MapServer"/>
            </esri:Map>
            <!--添加按钮-->
            <Button Content="书签" Name="Btn_SQ" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top" Width="75" RenderTransformOrigin="0,0" Click="Btn_SQ_Click_1"/>
            <Button Content="渲染" Name="Btn_XR" HorizontalAlignment="Left" Margin="10,50,0,0" Grid.Row="1" VerticalAlignment="Top" Width="75" RenderTransformOrigin="0,0" Click="Btn_XR_Click_1"  />
            <Button Content="查询" Name="Btn_CX" HorizontalAlignment="Left" Margin="10,93,0,0" VerticalAlignment="Top" Width="75" Click="Btn_CX_Click_1" />
            <!--添加导航条-->
            <esri:Navigation Map="{Binding ElementName=MyMap}" Grid.Column="1" HorizontalAlignment="Left" Margin="0,250,0,0" VerticalAlignment="Bottom" Height="120" Width="150"/>
            <!--添加导鹰眼-->
            <esri:OverviewMap HorizontalAlignment="Right" VerticalAlignment="Bottom" Map="{Binding ElementName=MyMap}" Grid.Column="1" Height="100" Width="100" Visibility="Visible" RenderTransformOrigin="0.65,0.8" >
            <esri:OverviewMap.Layer>
                    <esri:ArcGISDynamicMapServiceLayer ID="StreetLayer" Url="http://localhost/ArcGIS/rest/services/sczl/MapServer"/>
            </esri:OverviewMap.Layer>
            </esri:OverviewMap>
        </Grid>
        <!--添加书签-->
        <esri:Bookmark Name="书签" HorizontalAlignment="Left" Margin="100,0,0,0" Grid.Row="1" VerticalAlignment="Top" Visibility="Collapsed" Map="{Binding ElementName=MyMap}" />
        <!--添加进度条-->
        <esri:MapProgressBar Map="{Binding ElementName=MyMap}" HorizontalAlignment="Center" VerticalAlignment="Center" Height="30" Width="150" Visibility="Visible" Grid.Row="1"   />

IDBServices

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.Text;

namespace MyWebSite.Web
{
    // 注意: 使用“重构”菜单上的“重命名”命令，可以同时更改代码和配置文件中的接口名“IDBServices”。
    [ServiceContract]
    public interface IDBServices
    {
        [OperationContract]
        void DoWork();

        [OperationContract]
        bool CheckUser(string sUser,string sPsd);
    }
}

DBservuces

sing System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.Text;
using System.Data;
using System.Data.SqlClient;

namespace MyWebSite.Web
{
    // 注意: 使用“重构”菜单上的“重命名”命令，可以同时更改代码、svc 和配置文件中的类名“DBServices”。
    // 注意: 为了启动 WCF 测试客户端以测试此服务，请在解决方案资源管理器中选择 DBServices.svc 或 DBServices.svc.cs，然后开始调试。
    public class DBServices : IDBServices
    {
        private SqlConnection pSqlConn=null;
        private string sSqlConnString = "Data Source=D410-JS;Initial Catalog=webgis;Integrated Security=True";
        public void DoWork()
        {
        }
        /// <summary>
        /// 检查用户密码是否正确
        /// </summary>
        /// <param name="sUser"></param>
        /// <param name="sPsd"></param>
        /// <returns></returns>
        public bool CheckUser(string sUser, string sPsd)
        {
            try
            {
                //连接数据库
                if (CheckSQLConn())
                {
                    string sql = "select * from dbo.tb_UserInfo where UserName=‘{0}‘ and UserPsd=‘{1}‘";//表名  列名

                    sql = String.Format(sql, sUser, sPsd);
                    // 查询数据库里面的记录
                    SqlDataAdapter pSQLDataAdapter = new SqlDataAdapter(sql, pSqlConn);
                    DataSet pDataSet = new DataSet();

                    pSQLDataAdapter.Fill(pDataSet);

                    int ResultCount = pDataSet.Tables[0].Rows.Count;
                    //判断该记录是否存在
                    if (ResultCount > 0)
                    {
                        return true;
                    }
                    else
                    {
                        return false;
                    }
                }
                return false;
            }
            catch
            {
                return false;
            }

        }

        /// <summary>
        /// 连接数据库
        /// </summary>
        /// <returns></returns>
        private bool CheckSQLConn()
        {
            try
            {
                //判断连接是否存在
                if (pSqlConn == null)
                {
                    pSqlConn = new SqlConnection();
                    pSqlConn.ConnectionString = sSqlConnString;
                }
                //判断连接有没有开启
                if (pSqlConn.State != ConnectionState.Open)
                {
                    pSqlConn.Open();
                }
                return true;
            }
            catch
            {
                return false;
            }

        }
    }
}

MainPage

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using MyWebSite.DBServerSR;

namespace MyWebSite
{
    public partial class MainPage : UserControl
    {
        public MainPage()
        {
            InitializeComponent();
        }

        private void Login_Click_1(object sender, RoutedEventArgs e)
        {
            string sUserName = UserName.Text.Trim();
            string sUserPsd = UserPsd.Text.Trim();

            DBServicesClient pDBServiceClient = new DBServicesClient();
            //异步调用WCF服务
            pDBServiceClient.CheckUserAsync(sUserName, sUserPsd);
            pDBServiceClient.CheckUserCompleted += pDBServiceClient_CheckUserCompleted;

        }

        /// <summary>
        /// checkUser回调事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        void pDBServiceClient_CheckUserCompleted(object sender, CheckUserCompletedEventArgs e)
        {
            try
            {
                if (e.Result)
                {
                    MessageBox.Show("用户存在");
                }
                else
                {
                    MessageBox.Show("用户名或密码不正确");
                }
            }
            catch
            {
                MessageBox.Show("网络无法访问！");
            }

        }

        private void Cancel_Click_1(object sender, RoutedEventArgs e)
        {
            System.Windows.Browser.HtmlPage.Window.Invoke("close");
        }
    }
}