C# 从字符串数组创建sql查询

我的界面-

我正在尝试展开嵌套子查询-

select * from jobs where (location='delhi' or location='Mumbai') and profile in(select profile from jobs where profile='CompScience');

对于勾选的每个复选框，我想将其添加到条件中。 例如，如果勾选框为德里、孟买、康普科学

问题是-

select * from jobs where (location='delhi' or location='Mumbai') and profile in(select profile from jobs where profile='CompScience'); 

这是我的尝试-

private void button1_Click(object sender, EventArgs e)
{
    String location=null;
    string profile-null;

    if (checkBox1.Checked == true)
    {
        location+= checkBox1.Text;
    }

    if (checkBox2.Checked == true)
    {
        location += checkBox2.Text;
    }

    if (checkBox3.Checked == true)
    {
        location += checkBox3.Text;
    }

    if (checkBox4.Checked == true)
    {
        profile += checkBox4.Text;
    }

    if (checkBox5.Checked == true)
    {
        profile += checkBox5.Text;
    }

    if (checkBox6.Checked == true)
    {
        profile += checkBox6.Text;
    }

    //MessageBox.Show(location);

    db_CONNECT();
    conn.Open();

    try
    {
        String query = "select * from jobs where(location= 'delhi' or location = 'Mumbai') and profile in(select profile from jobs where profile = 'CompScience');";
        OracleCommand comm2 = new OracleCommand(selectquery, conn);
        OracleDataAdapter MyAdapter = new OracleDataAdapter();//adapter acts as interface btw database and dataset(which is collectio of tables)
        MyAdapter.SelectCommand = comm2;
        DataTable dTable = new DataTable();//datatable represents a single table in database 
        MyAdapter.Fill(dTable);
        dataGridView1.DataSource = dTable;
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }

    conn.Close();
}

我尝试连接字符串，然后从中提取单个元素

编辑-

---

您可以有一个复选框数组，并使用

string.join（）

：

如果在父容器（如groupbox或panel）上有复选框，您甚至可以执行以下操作：

CheckBox[] Locations = locPanel.Controls.OfType<CheckBox>().ToArray();
CheckBox[] Profiles = profPanel.Controls.OfType<CheckBox>().ToArray();

CheckBox[]Locations=locPanel.Controls.OfType（）.ToArray（）；
复选框[]Profiles=profPanel.Controls.OfType（）.ToArray（）；

然后，您可以通过以下方式创建查询命令（这只是针对

位置的示例，对于
配置文件
您应该采用相同的方式）：

根据Dmitry的回答，我建议将其进一步简化为

// ... do locations AND profiles the way Dmitry suggested

// start out with a generic query
StringBuilder querybuilder = new StringBuilder("SELECT * FROM jobs WHERE 1 = 1");

if (locations.Any())
{
    var locationsString = string.Join(", ", locations.Select(l => $"'{l}'"));
    querybuilder.AppendFormat(" AND location IN ({0})", locationsString);
}

if (profiles.Any())
{
    var profilesString = string.Join(", ", profiles.Select(l => $"'{l}'"));
    querybuilder.AppendFormat(" AND profile IN ({0})", profilesString);
}

// ...

OracleCommand comm2 = new OracleCommand(querybuilder.ToString(), conn);

catch all
其中1=1
是创建动态组合查询的普遍接受的方法，它允许您极大地简化将变量子句附加到查询中的条件。
为什么不在（）
中执行一个
位置？您当前的代码生成什么查询？明显的问题似乎是，您生成的查询缺少值周围的
“
。可能是重复的Im获取空元组。我在使用的编辑中附加了代码…可能是我做错了什么？@ubuntu\u noob您的复选框数组是空的吗？我在GUI@ubuntu_noob我创造了同样的环境，同样的代码对我有用。当你点击按钮时，复选框被选中了吗？你能再解释一下代码吗？我没有完全理解它
CheckBox[] Locations = locPanel.Controls.OfType<CheckBox>().ToArray();
CheckBox[] Profiles = profPanel.Controls.OfType<CheckBox>().ToArray();

List<string> locations = new List<string>();

private void button1_Click(object sender, EventArgs e)
{       
    if (checkBox1.Checked == true)
    {
        locations.Add(checkBox1.Text);
    }
    else
    {
        locations.Remove(checkBox1.Text);
    }
    // and so on for other locations
}

var locationsString = string.Join(", ", locations.Select(l => $"'{l}'"));  // this gives you, e.x. 'Delhi', 'Mumbai'

var query = "";
if (locations.Any())
{
    query = $"select * from jobs where(location in {locationsString }) and profile in(select profile from jobs where profile = 'CompScience');";
}
else
{
    query = $"select * from jobs where profile in(select profile from jobs where profile = 'CompScience');";
}

// ... do locations AND profiles the way Dmitry suggested

// start out with a generic query
StringBuilder querybuilder = new StringBuilder("SELECT * FROM jobs WHERE 1 = 1");

if (locations.Any())
{
    var locationsString = string.Join(", ", locations.Select(l => $"'{l}'"));
    querybuilder.AppendFormat(" AND location IN ({0})", locationsString);
}

if (profiles.Any())
{
    var profilesString = string.Join(", ", profiles.Select(l => $"'{l}'"));
    querybuilder.AppendFormat(" AND profile IN ({0})", profilesString);
}

// ...

OracleCommand comm2 = new OracleCommand(querybuilder.ToString(), conn);