C# 如何在SQL中检查值是1还是0?

C# 如何在SQL中检查值是1还是0?,c#,mysql,sql,.net,C#,Mysql,Sql,.net,所以我设置了数据库连接,它确实连接了。 现在我想检查表中的每一行列是否被激活是0还是1,因为它是位,但我不知道怎么做 我会执行一个查询吗?我是否将所有行存储在一个列表中,然后进行检查 using (var connection = new SqlConnection(cb.ConnectionString)) { try { connection.Open(); if (connection.State == ConnectionState.Ope

所以我设置了数据库连接,它确实连接了。 现在我想检查表中的每一行
列是否被激活
0
还是
1
,因为它是,但我不知道怎么做

我会执行一个查询吗?我是否将所有行存储在一个列表中,然后进行检查

using (var connection = new SqlConnection(cb.ConnectionString))
{
    try
    {
        connection.Open();
        if (connection.State == ConnectionState.Open)
        {
            Console.WriteLine("Connected!");
        }
        else
        {
            Console.WriteLine("Failed..");
        }
    }
    catch (Exception e)
    {
        Console.WriteLine(e);
        throw;
    }
}

我想你正在寻找这样的东西:

SqlConnection sqlConnection1 = new SqlConnection("Your Connection String");
SqlCommand cmd = new SqlCommand();
SqlDataReader reader;

cmd.CommandText = "SELECT * FROM Customers";
cmd.CommandType = CommandType.Text;
cmd.Connection = sqlConnection1;

sqlConnection1.Open();

reader = cmd.ExecuteReader();
// Data is accessible through the DataReader object here.

sqlConnection1.Close();
  using (var connection = new SqlConnection(cb.ConnectionString)) {
    try {
      connection.Open();

      // connection.Open() either succeeds (and so we print the message) 
      // or throw an exception; no need to check 
      Console.WriteLine("Connected!");

      //TODO: edit the SQL if required
      string sql =
        @"select IsActivated
            from MyTable";

      using (var query = new SqlCommand(sql, connection)) {
        using (var reader = query.ExecuteReader()) {
          while (reader.Read()) {
            // Now it's time to answer your question: let's read the value 
            //   reader["IsActivated"] - value of IsActivated as an Object
            //   Convert.ToBoolean     - let .Net do all low level work for you
            bool isActivated = Convert.ToBoolean(reader["IsActivated"]);

            // Uncomment, if you insist on 0, 1
            // int bit = Convert.ToInt32(reader["IsActivated"]);

            //TODO: field has been read into isActivated; put relevant code here  
          }
        }
      }
    }
    catch (DataException e) { // Be specific: we know how to process data errors only
      Console.WriteLine(e);

      throw;
    }
  }
摘自


SqlDataReader中应该包含所有数据,包括isactivated列,然后您可以检查其各自的值。

我想您正在寻找类似以下内容:

SqlConnection sqlConnection1 = new SqlConnection("Your Connection String");
SqlCommand cmd = new SqlCommand();
SqlDataReader reader;

cmd.CommandText = "SELECT * FROM Customers";
cmd.CommandType = CommandType.Text;
cmd.Connection = sqlConnection1;

sqlConnection1.Open();

reader = cmd.ExecuteReader();
// Data is accessible through the DataReader object here.

sqlConnection1.Close();
  using (var connection = new SqlConnection(cb.ConnectionString)) {
    try {
      connection.Open();

      // connection.Open() either succeeds (and so we print the message) 
      // or throw an exception; no need to check 
      Console.WriteLine("Connected!");

      //TODO: edit the SQL if required
      string sql =
        @"select IsActivated
            from MyTable";

      using (var query = new SqlCommand(sql, connection)) {
        using (var reader = query.ExecuteReader()) {
          while (reader.Read()) {
            // Now it's time to answer your question: let's read the value 
            //   reader["IsActivated"] - value of IsActivated as an Object
            //   Convert.ToBoolean     - let .Net do all low level work for you
            bool isActivated = Convert.ToBoolean(reader["IsActivated"]);

            // Uncomment, if you insist on 0, 1
            // int bit = Convert.ToInt32(reader["IsActivated"]);

            //TODO: field has been read into isActivated; put relevant code here  
          }
        }
      }
    }
    catch (DataException e) { // Be specific: we know how to process data errors only
      Console.WriteLine(e);

      throw;
    }
  }
摘自


SqlDataReader中应该包含您的所有数据,包括您的isactivated列,然后您可以检查其各自的值。

如果您想读取字段,您可以实现如下操作:

SqlConnection sqlConnection1 = new SqlConnection("Your Connection String");
SqlCommand cmd = new SqlCommand();
SqlDataReader reader;

cmd.CommandText = "SELECT * FROM Customers";
cmd.CommandType = CommandType.Text;
cmd.Connection = sqlConnection1;

sqlConnection1.Open();

reader = cmd.ExecuteReader();
// Data is accessible through the DataReader object here.

sqlConnection1.Close();
  using (var connection = new SqlConnection(cb.ConnectionString)) {
    try {
      connection.Open();

      // connection.Open() either succeeds (and so we print the message) 
      // or throw an exception; no need to check 
      Console.WriteLine("Connected!");

      //TODO: edit the SQL if required
      string sql =
        @"select IsActivated
            from MyTable";

      using (var query = new SqlCommand(sql, connection)) {
        using (var reader = query.ExecuteReader()) {
          while (reader.Read()) {
            // Now it's time to answer your question: let's read the value 
            //   reader["IsActivated"] - value of IsActivated as an Object
            //   Convert.ToBoolean     - let .Net do all low level work for you
            bool isActivated = Convert.ToBoolean(reader["IsActivated"]);

            // Uncomment, if you insist on 0, 1
            // int bit = Convert.ToInt32(reader["IsActivated"]);

            //TODO: field has been read into isActivated; put relevant code here  
          }
        }
      }
    }
    catch (DataException e) { // Be specific: we know how to process data errors only
      Console.WriteLine(e);

      throw;
    }
  }

如果要读取字段,可以实现如下操作:

SqlConnection sqlConnection1 = new SqlConnection("Your Connection String");
SqlCommand cmd = new SqlCommand();
SqlDataReader reader;

cmd.CommandText = "SELECT * FROM Customers";
cmd.CommandType = CommandType.Text;
cmd.Connection = sqlConnection1;

sqlConnection1.Open();

reader = cmd.ExecuteReader();
// Data is accessible through the DataReader object here.

sqlConnection1.Close();
  using (var connection = new SqlConnection(cb.ConnectionString)) {
    try {
      connection.Open();

      // connection.Open() either succeeds (and so we print the message) 
      // or throw an exception; no need to check 
      Console.WriteLine("Connected!");

      //TODO: edit the SQL if required
      string sql =
        @"select IsActivated
            from MyTable";

      using (var query = new SqlCommand(sql, connection)) {
        using (var reader = query.ExecuteReader()) {
          while (reader.Read()) {
            // Now it's time to answer your question: let's read the value 
            //   reader["IsActivated"] - value of IsActivated as an Object
            //   Convert.ToBoolean     - let .Net do all low level work for you
            bool isActivated = Convert.ToBoolean(reader["IsActivated"]);

            // Uncomment, if you insist on 0, 1
            // int bit = Convert.ToInt32(reader["IsActivated"]);

            //TODO: field has been read into isActivated; put relevant code here  
          }
        }
      }
    }
    catch (DataException e) { // Be specific: we know how to process data errors only
      Console.WriteLine(e);

      throw;
    }
  }

检查您的行,然后对它们做什么?@常规
我想检查表中的每一行,列是被激活的是0还是1,因为它有点
,没有回答我的问题,您想数一数吗,您想过滤我的字段吗,你只想检查一下是否存在这是迄今为止初学者最多的问题,任何一个初学者教程都能回答这个问题。没有人天生就具备你需要学习的所有知识。检查你的行,然后用它们做什么?@TheGeneral
我想检查我表格中的每一行,列是被激活的是0还是1,因为它有点不符合我的问题,你想数一数吗,你想过滤我的这个字段吗,你只想检查一下是否存在这是迄今为止初学者最多的问题,任何一个初学者教程都能回答这个问题。没有人天生就拥有你需要学习的所有知识。