如何在组合框中不显示空对象 [英] How to don't display null object in combobox

问题描述

大家好，

我的框架：visual studio 2008 + sql server 2005



我有自己的数据库。它有col1栏：

row1：faefe1

row2：faefe1

row3：null

row4： faefe2

row5：faefe2

row6：null

row7：null

row8：faefe1

row9：faefe1

我的窗口表单应用程序包括1个组合框控件，它被限制在上面的数据库中：

hello everyone,
my framework: visual studio 2008 + sql server 2005

I had my own database. it have "col1" column:
row1:faefe1
row2:faefe1
row3:null
row4:faefe2
row5:faefe2
row6:null
row7:null
row8:faefe1
row9:faefe1
my window form application include 1 combobox control, it is bounded to above database:

DataView dv_filename = new DataView();
dv_filename.Table = table;
comboBox1.DataSource = dv_filename;
comboBox1.DisplayMember = "col1";

上面的组合框显示声明。

如何显示它（意味着删除空对象）：

row1： faefe1

row2：faefe1

row3：faefe2

row4：faefe2

row5：faefe1

row6：faefe1



请帮帮我。非常感谢！

combobox dislay as above declare.
how to display it as (mean that remove null object):
row1:faefe1
row2:faefe1
row3:faefe2
row4:faefe2
row5:faefe1
row6:faefe1

please help me. thank you very much!

推荐答案

表，我猜你是通过执行一些查询得到的。因此，您需要更新该查询以包含Where条件，例如......

The table, I guess you got by executing some query. So, you need to update that query to include a Where condition something like...

SELECT col1 
FROM
    TableName
WHERE
    Col1 <> ''

在你的查询，将null或空转换为空白并在下拉列表中显示值。

In your query, convert null or empty into an empty space and display values in the dropdown.

您可以尝试通过过滤绑定组合框的表中的空值。请尝试如下：

you can try by filtering the null values from the table you are binding your combo box with. Try as below:

DataView dv_filename = new DataView();
var table1 = from t in table 
             where t.col1 != NULL
             select t;
dv_filename.Table = table1;
comboBox1.DataSource = dv_filename;
comboBox1.DisplayMember = "col1";

或者您可以在数据库中执行相同操作类似这样的事情：

or you can do the same in DB from where you are getting the table something like this:

select colms from table where col1 IS NOT Null;

这篇关于如何在组合框中不显示空对象的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！