Question

我正在尝试制作一个包含多个Comboboxes的搜索过滤器，代码工作，但只是在第一次测试中，问题是当我想在datagirdview上显示任何内容后进行另一次搜索时。这是代码，我不知道这个问题是什么？

string aFilter = string.Empty;
string bFilter = string.Empty;
string cFilter = string.Empty;

private void applyFilter()
{
    generateFilter(bFilter);
    generateFilter(cFilter);
}

private void generateFilter(string filter)
{
    if (!string.IsNullOrEmpty(filter))
    {
        if (string.IsNullOrEmpty(aFilter))
        {
            aFilter = filter;
        }
        else
        {
            aFilter += " AND " + filter;
        }
    }
}

private void comboBox2_SelectedIndexChanged(object sender, EventArgs e)
{
    DataView dv = new DataView(table);
    bFilter = string.Format("[Nom complet] LIKE '%{0}%'", comboBox2.SelectedItem.ToString());
    applyFilter();
    dv.RowFilter = aFilter;
    dataGridView1.DataSource = dv;
}

private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
    DataView dv1 = new DataView(table);
    cFilter = string.Format("[Type programme] LIKE '%{0}%'", comboBox1.SelectedItem.ToString());
    applyFilter();
    dv1.RowFilter = aFilter;
    dataGridView1.DataSource = dv1;
}

Answer 1

问题是aFilter。每个过滤器一次又一次地添加到它。

尝试：

string bFilter = "";
string cFilter = "";

private string CombinFilters()
{
    var a = new[] { bFilter, cFilter }; //all filters to combin
    var notNull = a.Where(x => !string.IsNullOrWhiteSpace(x));

    if (notNull.Any())
        return string.Join(" AND ", notNull);
    else
        return null;
}

private void comboBox2_SelectedIndexChanged(object sender, EventArgs e)
{
    DataView dv = new DataView(table);
    bFilter = string.Format("[Nom complet] LIKE '%{0}%'", "123");
    dv.RowFilter = CombinFilters();
    dataGridView1.DataSource = dv;
}

private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
    DataView dv = new DataView(table);
    cFilter = string.Format("[Type programme] LIKE '%{0}%'", "345");
    dv.RowFilter = CombinFilters();
    dataGridView1.DataSource = dv;
}

搜索过滤器有多个Comboboxes？

1 个答案: