C＃在组合框中查看显示成员 [英] C# viewing display member in combobox

问题描述

我是c＃数据库编程的新手，我正在设计一个具有组合框的简单表单，这些表单是绑定的，当我通过记录导航时，组合框的显示成员有时不会显示，而是显示值成员任何想法为什么它正在发生。



我的尝试：

这是我写的代码：
 
 private void Frm_R_Load（object sender，EventArgs e）
 {
 #region表格加载
 this.land_NewTableAdapter.Fill （reentitiesDataset.Land_New）; 
 FillCombos（T_Region，id_RegionComboBox）; 
 FillCombos（T_district，id_DistrictComboBox）; 
 #endregion 
} 
 
 private void FillCombos（String TableName，ComboBox ComboName）
 {
 using（SqlConnection conn = new SqlConnection（string.Format（ ConnectionString.DatabaseConnection.GetSQLConnString（））））
 {
 try 
 {
 conn.Open（）; 
 SqlCommand cmdCombo = new SqlCommand（FillCombos，conn）; 
 cmdCombo.CommandType = CommandType.StoredProcedure; 
 cmdCombo.Parameters.Add（@ TableName，SqlDbType.VarChar）.Value = TableName; 
 
 SqlDataAdapter DaCombo = new SqlDataAdapter（cmdCombo）; 
 DataSet DsCombo = new DataSet（）; 
 DaCombo.Fill（DsCombo）; 
 
 ComboName.DataSource = DsCombo.Tables [0]; 
 ComboName.DisplayMember =Descrp; 
 ComboName.ValueMember =Id; 
 
} 
 catch（exception ex）
 {
 MessageBox.Show（ex.Message，，MessageBoxButtons.OK，MessageBoxIcon.Error）; 
} 
} 
} 
 
这是程序：
 
 PROCEDURE [dbo]。[FillCombos]（@ TableName as varchar （100））
 AS 
 BEGIN 
声明@SQL为varchar（1000）
 SET NOCOUNT ON; 
设置@SQL ='从'+ @TableName +'中选择Id，Descrp 2'
 exec sp_sqlexec @sql 
 END 
表的结构：
 
 CREATE TABLE [dbo]。[T_District]（[Id] [tinyint] IDENTITY（1,1）NOT NULL，[varrp]（50）NOT NULL，CONSTRAINT [PK_T_District] PRIMARY KEY CLUSTERED（[创建] ASC）WITH（ALLOW_ROW_LOCKS = ON，ALLOW_PAGE_LOCKS = ON）ON [PRIMARY]）ON [PRIMARY] CREATE TABLE [dbo]。[T_Region]（[Id] [bigint] IDENTITY（1,1）NOT NULL，[Desccript] ] [varchar]（255）NOT NULL，[D2] [varchar]（255）NULL，CONSTRAINT [PK_T_Region] PRIMARY KEY CLUSTERED（[Id] ASC）WITH（ALLOW_ROW_LOCKS = ON，ALLOW_PAGE_LOCKS = ON）ON [PRIMARY]）ON [主要] 

解决方案

我不确定你的代码是如何工作的但我会使用绑定和WPF（如果那是你的选项） - 有关于此的文章：

一步一步与组合框的WPF数据绑定 [ ^ ]



......无论如何你都会遇到像UWP这样的东西......

I am new to c# database programming, and am designing a simple form that has comboboxes, which are binded and when I navigate thru records the display member of the combobox do not show sometimes and displays instead the value member any idea why it is happening.

What I have tried:

This is the code am writing:

private void Frm_R_Load(object sender, EventArgs e)
{
   #region Form load
   this.land_NewTableAdapter.Fill(reentitiesDataset.Land_New);
   FillCombos("T_Region", id_RegionComboBox);
   FillCombos("T_district", id_DistrictComboBox);
   #endregion
}

private void FillCombos(String TableName, ComboBox ComboName)
{
    using (SqlConnection conn = new SqlConnection(string.Format(ConnectionString.DatabaseConnection.GetSQLConnString())))
    {
        try
        {
        conn.Open();
        SqlCommand cmdCombo = new SqlCommand("FillCombos", conn);
        cmdCombo.CommandType = CommandType.StoredProcedure;
        cmdCombo.Parameters.Add("@TableName", SqlDbType.VarChar).Value = TableName;

        SqlDataAdapter DaCombo = new SqlDataAdapter(cmdCombo);
        DataSet DsCombo = new DataSet();
        DaCombo.Fill(DsCombo);

        ComboName.DataSource = DsCombo.Tables[0];
        ComboName.DisplayMember = "Descrp";
        ComboName.ValueMember = "Id";

       }
       catch (Exception ex)
       {
           MessageBox.Show(ex.Message, " ", MessageBoxButtons.OK, MessageBoxIcon.Error);
        }
    }
}

And this is the procedure:

PROCEDURE [dbo].[FillCombos](@TableName as varchar(100))
AS
BEGIN
    Declare @SQL as varchar(1000)
    SET NOCOUNT ON;
    Set @SQL = 'Select Id,Descrp  from ' + @TableName + ' order by 2 '
    exec sp_sqlexec @sql
END
Structure of the tables:

CREATE TABLE [dbo].[T_District]( [Id] [tinyint] IDENTITY(1,1) NOT NULL, [Descrp] [varchar](50) NOT NULL, CONSTRAINT [PK_T_District] PRIMARY KEY CLUSTERED ( [Descrp] ASC )WITH (ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] CREATE TABLE [dbo].[T_Region]( [Id] [bigint] IDENTITY(1,1) NOT NULL, [Descrp] [varchar](255) NOT NULL, [D2] [varchar](255) NULL, CONSTRAINT [PK_T_Region] PRIMARY KEY CLUSTERED ( [Id] ASC )WITH (ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY]

解决方案

I am not sure how your code works but I would use binding and WPF (if thats an option for you) - there are tones of articles around this:
Step by Step WPF Data Binding with Comboboxes[^]

... and you'll be running into it with things like UWP anyway...

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