如何在一列中的两个文本框之间创建SqlFilter答案

【问题标题】：how to CreateSqlFilter between two textbox in one column如何在一列中的两个文本框之间创建SqlFilter
【发布时间】：2019-01-13 10:23:59
【问题描述】：

现在我使用此代码在 datagridview 中制作过滤器

private void Button1_Click(object sender, EventArgs e)
    {
        SqlCommand selectCommand = new SqlCommand();

        var filterConditions = new[] {
    CreateSqlFilter("Name_Arabic", txtName_Arabic, selectCommand, false),
    CreateSqlFilter("gender", CBgender, selectCommand, false),
    CreateSqlFilter("CIVILIDD", txtCIVILIDD, selectCommand, true),
    CreateSqlFilter("status", comboBox1, selectCommand, false),
    CreateSqlFilter("username", txtusername, selectCommand, false),
    CreateSqlFilter("City", comboBoxCity, selectCommand, false),
    CreateSqlFilter("Governorate", comboBoxGovernorate, selectCommand, false),
    CreateSqlFilter("confirmation", comboBox2, selectCommand, false),
    CreateSqlFilter("NATIONALITY", CBNATIONALITY, selectCommand, false)
    // etc.
};

        string filterCondition = filterConditions.Any(a => a != null) ? filterConditions.Where(a => a != null).Aggregate((filter1, filter2) => String.Format("{0} AND {1}", filter1, filter2)) : (string)null;

        using (var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["my"].ConnectionString))
        {
            selectCommand.Connection = connection;
            selectCommand.CommandText = filterCondition == null ? "SELECT * FROM tabl2" : "SELECT * FROM tabl2 WHERE " + filterCondition;
            connection.Open();
            SqlDataAdapter adapter = new SqlDataAdapter(selectCommand);
            DataTable dataSource = new DataTable();
            adapter.Fill(dataSource);
            dataGridView1.DataSource = dataSource;
        }
    }

    private string CreateSqlFilter(string fieldName, Control userInputControl, SqlCommand command, bool exactMatch)
    {
        string searchValue = null;
        if (userInputControl is TextBox) searchValue = ((TextBox)userInputControl).Text;
        if (userInputControl is ComboBox) searchValue = ((ComboBox)userInputControl).Text;
        if (String.IsNullOrWhiteSpace(searchValue)) return null;

        if (exactMatch)
        {
            command.Parameters.Add(new SqlParameter("@" + fieldName, searchValue));
            return fieldName + " = @" + fieldName;
        }
        else
        {
            command.Parameters.Add(new SqlParameter("@" + fieldName, "%" + searchValue + "%"));
            return fieldName + " LIKE @" + fieldName;
        }
    }

我想向它们添加两个文本框以在同一列（年龄）中进行过滤

【问题讨论】：

标签： c# filter datagridview

【解决方案1】：

我认为您很清楚最终您需要以下 SQL 条件之一：

age BETWEEN @ageFrom AND @ageTo
// OR
age >= @ageFrom AND age <= @ageTo

但我不建议您扩展您的 CreateSqlFilter 方法，因为使所有内容通用并不是一个好习惯。您可以简单地创建另一个方法来构建您的过滤条件。

另外，我建议您从查询构建器中删除 Control userInputControl 参数并改为接受 string value。这将使您的方法独立于 WinForms 命名空间。

更新

CreateRangeSqlFilter("age", tbAgeFrom.Text, tbAgeTo.Text, selectCommand),

private string CreateRangeSqlFilter(string fieldName, string from, string to, SqlCommand command)
{
    command.Parameters.Add(new SqlParameter("@" + fieldName + "From", from));
    command.Parameters.Add(new SqlParameter("@" + fieldName + "To", to));
    return $"{fieldName} BETWEEN @{fieldName}From AND @{fieldName}To";
}

更新 2

 private string CreateSqlFilter(string fieldName, Control userInputControl, SqlCommand command, bool exactMatch,
     bool isRange = false, Control userInputControl2 = null)
 {
     if (isRange)
     {
         string searchValue1 = null;
         if (userInputControl is TextBox) searchValue1 = ((TextBox)userInputControl).Text;
         if (userInputControl is ComboBox) searchValue1 = ((ComboBox)userInputControl).Text;

         string searchValue2 = null;
         if (userInputControl2 is TextBox) searchValue2 = ((TextBox)userInputControl2).Text;
         if (userInputControl2 is ComboBox) searchValue2 = ((ComboBox)userInputControl2).Text;
         if (String.IsNullOrWhiteSpace(searchValue1) && String.IsNullOrWhiteSpace(searchValue2)) return null;

         if (!String.IsNullOrWhiteSpace(searchValue1) && !String.IsNullOrWhiteSpace(searchValue2))
         {
             command.Parameters.Add(new SqlParameter("@" + fieldName + "From", searchValue1));
             command.Parameters.Add(new SqlParameter("@" + fieldName + "To", searchValue2));
             return $"{fieldName} BETWEEN @{fieldName}From AND @{fieldName}To";
         }

         if (!String.IsNullOrWhiteSpace(searchValue1))
         {
             command.Parameters.Add(new SqlParameter("@" + fieldName + "From", searchValue1));
             return $"{fieldName} >= @{fieldName}From";
         }

         command.Parameters.Add(new SqlParameter("@" + fieldName + "To", searchValue2));
         return $"{fieldName} <= @{fieldName}To";
     }

     string searchValue = null;
     if (userInputControl is TextBox) searchValue = ((TextBox)userInputControl).Text;
     if (userInputControl is ComboBox) searchValue = ((ComboBox)userInputControl).Text;
     if (String.IsNullOrWhiteSpace(searchValue)) return null;

     if (exactMatch)
     {
         command.Parameters.Add(new SqlParameter("@" + fieldName, searchValue));
         return fieldName + " = @" + fieldName;
     }
     else
     {
         command.Parameters.Add(new SqlParameter("@" + fieldName, "%" + searchValue + "%"));
         return fieldName + " LIKE @" + fieldName;
     }
 }

【讨论】：

如果我想扩展它有什么方法添加它
对不起，我反对。创建CreateSqlFilter 方法的副本并将其命名为CreateRangeSqlFilter。然后适当修改（接受ageFrom和ageTo值并生成SQL条件）
对不起，我还是不知道该怎么做
@AhmedAlKhteeb 请参阅我的帖子中的示例
@AhmedAlKhteeb 请参阅更新 2 部分。用法是CreateSqlFilter("age", tbAgeFrom, selectCommand, false, true, tbAgeTo)

【解决方案2】：

有两种不同的方法可以做到这一点，而无需每次都执行查询。

亮点：

过滤器：

完整的源代码可在： https://github.com/KohrAhr/XTask/blob/master/Wpf.MainApp/Functions/Functions.DataGrid.cs

【讨论】：