Question

我想使用两个不同的文本框来过滤数据库中的信息，以显示棒球运动员的平均分数。选择0,3到0.4的示例应该显示具有这些数字之间分数的玩家。

什么不起作用的是以下代码：

// Search for player, working
private void button1_Click(object sender, EventArgs e)
        {
            view.RowFilter = "LastName like '%" + textBox1.Text + "%'";
            if (textBox1.Text == "") view.RowFilter = string.Empty;
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            DataTable datatable = new DataTable();
            SqlConnection connection = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=C:\Users\Mattias\Dropbox\C#\Database\Baseball.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True");
            connection.Open();
            datatable.Load(new SqlCommand("select * from players", connection).ExecuteReader());
            dataGridView1.DataSource = view = datatable.DefaultView;
            connection.Close();
        }
// This button is not working
        private void button2_Click(object sender, EventArgs e)
        {
            decimal minimum = Convert.ToDecimal(textBox2.Text);
            decimal maximum = Convert.ToDecimal(textBox3.Text);
// Should display players with different scores
            view.RowFilter = String.Format("BattingAverage >= {0} AND BattingAverage <= {1}"
                , minimum, maximum);

            if (textBox2.Text == "") view.RowFilter = string.Empty;
            if (textBox3.Text == "") view.RowFilter = string.Empty;
        }

Answer 1

RowFilter不支持BETWEEN运算符。它也不支持像你这样的完整的SQL查询。但是，您可以在那里指定WHERE - 子句来过滤视图的行：

view.RowFilter = String.Format(CultureInfo.InvariantCulture.NumberFormat,
                 "BattingAverage >= {0} AND BattingAverage <= {1}", minimum, maximum);

我在InvariantCulture.NumberFormat中使用String.Format来确保RowFilter中所需的英文格式（点为小数点分隔符）。

请注意，您还使用撇号包装值，这些数字不允许使用数字，并且您使用textBox2.Text作为最小和最大值的输入。

Answer 2

现在可以通过添加CultureInfo来实现。 //搜索播放器，正在工作 private void button1_Click（object sender，EventArgs e） { view.RowFilter =“LastName like'％”+ textBox1.Text +“％'”; if（textBox1.Text ==“”）view.RowFilter = string.Empty; }

    private void Form1_Load(object sender, EventArgs e)
    {
        DataTable datatable = new DataTable();
        SqlConnection connection = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=C:\Users\Mattias\Dropbox\C#\Database\Baseball.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True");
        connection.Open();
        datatable.Load(new SqlCommand("select * from players", connection).ExecuteReader());
        dataGridView1.DataSource = view = datatable.DefaultView;
        connection.Close();
    }

// 正在使用CultureInfo private void button2_Click（object sender，EventArgs e） { decimal minimum = Convert.ToDecimal（textBox2.Text）; decimal maximum = Convert.ToDecimal（textBox3.Text）; //应该显示不同分数的玩家 view.RowFilter = String.Format（CultureInfo.InvariantCulture.NumberFormat ，（“BattingAverage＆gt; = {0} AND BattingAverage＆lt; = {1}” ，最小，最大）;

        if (textBox2.Text == "") view.RowFilter = string.Empty;
        if (textBox3.Text == "") view.RowFilter = string.Empty;
    }

Rowfilter与多个文本框

2 个答案: