我想请教一个问题 就是关于在WinForm C#里面的一个DataTable的过滤问题

Question

我要做一个库存查询功能 我想对我查询出来的数据 进行一个过滤  把库存量为0的那一条数据给隐藏掉 
我在窗体上 弄了个CheckBox控件来 在CheckBox控件的单击事件里实现这个效果 代码如下private void ckb_ShangPinCheck_Click(object sender, EventArgs e)
        {
            DataView dv = new DataView(tab);
            if (ckb_ShangPinCheck.Checked)
            { 
                dv.RowFilter= "库存量>0";
            }
            else
            {
                dv.RowFilter = "true";
            }
        }
可是执行了后没反应 本来我是没有转成 DataView的 如果直接DataTable来过滤的话 过滤是可以 但是 后续的问题好麻烦 因为多次点击后我的数据绑定控件会变下面提供相关的代码：private void Frm_Select_CangKu_Load(object sender, EventArgs e)//窗体加载事件
        {
            Query_CangKu(1);
        }
void Query_CangKu(int index)//这是执行绑定的方法
        {
            if (index == 1)
            {
                tab = bll_CangKu.Query_CangKu_BHMC("1", "", "", "");
                if (tab.Rows.Count != 0)
                {
                    if (tab.Rows.Count < 15)
                    {
                        int count = tab.Rows.Count;
                        for (int i = 0; i < (15 - count); i++)
                        {
                            tab.DefaultView.AddNew();
                        }
                        this.Dgdv_CangKu.DataSource = tab.DefaultView;
                    }
                    else
                    {
                        this.Dgdv_CangKu.DataSource = tab.DefaultView;
                    }
                }
                else
                {
                    for (int i = 0; i < 25; i++)
                    {
                        tab.DefaultView.AddNew();
                    }
                    this.Dgdv_CangKu.DataSource = tab.DefaultView;
                }
            }
            else
            {
                try
                {
                    if (cmb_CangKu.SelectedIndex == 0 && txt_Type.Text == "所有类别" && txt_BH_MC.Text == string.Empty)
                    {
                        tab = bll_CangKu.Query_CangKu_BHMC("1", "", "", "");
                    }
                    else if (cmb_CangKu.SelectedIndex != 0 && txt_Type.Text == "所有类别" && txt_BH_MC.Text == string.Empty)
                    {
                        tab = bll_CangKu.Query_CangKu_BHMC("1", cmb_CangKu.SelectedValue.ToString(), "", "");
                    }
                    else if (cmb_CangKu.SelectedIndex == 0 && txt_Type.Text != "所有类别" && txt_BH_MC.Text == string.Empty)
                    {
                        tab = bll_CangKu.Query_CangKu_BHMC("1", "", TypeID, "");
                    }
                    else if (cmb_CangKu.SelectedIndex == 0 && txt_Type.Text == "所有类别" && txt_BH_MC.Text != string.Empty)
                    {
                        tab = bll_CangKu.Query_CangKu_BHMC("1", "", "", txt_BH_MC.Text.Trim().ToString());
                    }
                    else if (cmb_CangKu.SelectedIndex == 0 && txt_Type.Text != "所有类别" && txt_BH_MC.Text != string.Empty)
                    {
                        tab = bll_CangKu.Query_CangKu_BHMC("1", "", TypeID, txt_BH_MC.Text.Trim().ToString());
                    }
                    else if (cmb_CangKu.SelectedIndex != 0 && txt_Type.Text != "所有类别" && txt_BH_MC.Text == string.Empty)
                    {
                        tab = bll_CangKu.Query_CangKu_BHMC("1", cmb_CangKu.SelectedValue.ToString(), TypeID, "");
                    }
                    else if (cmb_CangKu.SelectedIndex != 0 && txt_Type.Text != "所有类别" && txt_BH_MC.Text != string.Empty)
                    {
                        tab = bll_CangKu.Query_CangKu_BHMC("1", cmb_CangKu.SelectedValue.ToString(), TypeID, txt_BH_MC.Text.Trim().ToString());
                    }
                    else if (cmb_CangKu.SelectedIndex != 0 && txt_Type.Text == "所有类别" && txt_BH_MC.Text != string.Empty)
                    {
                        tab = bll_CangKu.Query_CangKu_BHMC("1", cmb_CangKu.SelectedValue.ToString(), "", txt_BH_MC.Text.Trim().ToString());
                    }
                    if (tab.Rows.Count != 0)
                    {
                        if (tab.Rows.Count < 15)
                        {
                            int count = tab.Rows.Count;
                            for (int i = 0; i < (15 - count); i++)
                            {
                                tab.DefaultView.AddNew();
                            }
                            this.Dgdv_CangKu.DataSource = tab.DefaultView;
                        }
                        else
                        {
                            this.Dgdv_CangKu.DataSource = tab.DefaultView;
                        }
                    }
                    else
                    {
                        for (int i = 0; i < 15; i++)
                        {
                            tab.DefaultView.AddNew();
                        }
                        this.Dgdv_CangKu.DataSource = tab;
                    }
                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.ToString(), "系统提示");
                }
            }
        }请路过的高手们 帮忙解决下这个问题 谢谢了 在线等

Answer 1

                dv.RowFilter= "库存量>0";这样应该可以吧？
 
这个可能不行，清空应该就可以了
                dv.RowFilter = "true";
                dv.RowFilter = "";

Answer 2

弄一个Form
拉上来一个控件DataGridView和一个CheckBox
声明一个全局的DataTable对象private DataTable dt = null;
在FormLoad的时候写如下代码
dt = new DataTable();
dt.Columns.Add("test1");
dt.Columns.Add("test2");
dt.Columns.Add("test3");
for (int i = 0; i < 10; i++)
{
    DataRow row = dt.NewRow();
    row["test1"] = "test1" + i;
    dt.Rows.Add(row);
}
DataView dv = new DataView(dt);
this.dataGridView1.DataSource = dv;然后在CheckBox的CheckedChanged事件中写下如下代码
DataView dv = new DataView(dt);
if (this.checkBox1.Checked)
{
    dv.RowFilter = "test1 > 'test13'";
}
this.dataGridView1.DataSource = dv;好了，你可以测试了~~~另外你还可以使用DataTable的Select方法
不过这个方法返回的是DataRow[]
你可以这样
DataRow[] rows = dt.Select("你的条件");
DataTable table = dt.Clone();
foreach(DataRow in rows)
{
    table.ImportRow(row);
}
然后把table绑定到控件就可以了
你只要记住，原来的数据源不要去改变，就可以了~~~

Answer 3

或者上面CheckedChanged的代码可以写成如下
DataView dv = this.dataGridView1.DataSource as DataView;
if (this.checkBox1.Checked)
{
    dv.RowFilter = "test1 > 'test13'";
}
else
{
    dv.RowFilter = "";
}

Answer 4

private void ckb_ShangPinCheck_Click(object sender, EventArgs e)
        {
            DataView dv = tab.DefaultView;   //与GridView绑定的DataView
            if (ckb_ShangPinCheck.Checked)
            { 
                dv.RowFilter= "库存量>0";
            }
            else
            {
                dv.RowFilter = "true";
            }
        }

Answer 5

你搜素得到的ds
ds.Tables[0].Select("库存量>0");

Answer 6

lovefootball的方法可以DataRow[] rows = dt.Select("你的条件"); 
DataTable table = dt.Clone(); 
foreach(DataRow in rows) 
{ 
    table.ImportRow(row); 
} 
比用其他方法都要好 现在就是隐藏了后啊 因为我只有拿1条数据做测试  我的DataGridView控件会只剩下标题 我在绑定的时候 就是为了防止出现这种情况 在绑定之前就先判断了Count 如果少于15条 就通过循环添加空白行if (tab.Rows.Count != 0)
                    {
                        if (tab.Rows.Count < 15) 如果数据少月15条
                        {
                            int count = tab.Rows.Count;
                            for (int i = 0; i < (15 - count); i++)就循环添加空白数据项 
                            {
                                tab.DefaultView.AddNew();
                            }
                            this.Dgdv_CangKu.DataSource = tab.DefaultView;
                        }
                        else
                        {
                            this.Dgdv_CangKu.DataSource = tab.DefaultView;
                        }
                    }
                    else
                    {
                        for (int i = 0; i < 15; i++)
                        {
                            tab.DefaultView.AddNew();
                        }
                        this.Dgdv_CangKu.DataSource = tab;
                    }这样就不会使窗体太难看 始终有网格存在 这样更美观一些

Answer 7

用FOREACH遍历datatable的每一行吧

Answer 8

private void ckb_ShangPinCheck_Click(object sender, EventArgs e)
        {
            DataView dv = tab.defaultview;
            if (ckb_ShangPinCheck.Checked)
            { 
                dv.RowFilter= "库存量>0";
            }
            else
            {
                dv.RowFilter = "";
            }
            //再进行绑定，
        }

Answer 9

呵呵 终于被我自己给解决了 谢谢大家的参与 我把我的解决方法贴出来 大家看下  private void ckb_ShangPinCheck_Click(object sender, EventArgs e)
        {
            if (ckb_ShangPinCheck.Checked)
            {
                DataRow[] rows = tab.Select("库存量>0");
                DataTable table = tab.Clone();
                foreach (DataRow row in rows)
                {
                    table.ImportRow(row);
                }
                if (table.Rows.Count > 0)
                {
                    if (table.Rows.Count < 20)
                    {
                        int count = table.Rows.Count;
                        for (int i = 0; i < (20 - count); i++)
                        {
                            table.DefaultView.AddNew();
                        }
                        this.Dgdv_CangKu.DataSource = table.DefaultView;
                    }
                    else
                    {
                        this.Dgdv_CangKu.DataSource = table.DefaultView;
                    }
                }
                else
                {
                    for (int i = 0; i < 20; i++)
                    {
                        table.DefaultView.AddNew();
                    }
                    this.Dgdv_CangKu.DataSource = table.DefaultView;
                }
            }
            else
            {
                this.Dgdv_CangKu.DataSource = tab;
            }
        }效果是实现了 而且感觉还不错 但是大家如果有更好的实现方法 就一定要告诉我哦