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SQLクエリからカウントをキャプチャする

SQLコマンドからカウントを取得するC＃（.csファイル）で最も簡単な方法は何ですか

SELECT COUNT(*) FROM table_name

int変数に？

c#sqlsql-server
45
Sebastjan

SqlCommand.ExecuteScalar() を使用して、intにキャストします。

cmd.CommandText = "SELECT COUNT(*) FROM table_name";
Int32 count = (Int32) cmd.ExecuteScalar();
95
m.edmondson
SqlConnection conn = new SqlConnection("ConnectionString");
conn.Open();
SqlCommand comm = new SqlCommand("SELECT COUNT(*) FROM table_name", conn);
Int32 count = (Int32) comm .ExecuteScalar();
20
Rami Shareef

変換エラーが発生します：

cmd.CommandText = "SELECT COUNT(*) FROM table_name";
Int32 count = (Int32) cmd.ExecuteScalar();

代わりに使用します：

string stm = "SELECT COUNT(*) FROM table_name WHERE id="+id+";";
MySqlCommand cmd = new MySqlCommand(stm, conn);
Int32 count = Convert.ToInt32(cmd.ExecuteScalar());
if(count > 0){
    found = true; 
} else {
    found = false; 
}
9
Andrew Kralovec

SQLを使用したC＃の補完：

SqlConnection conn = new SqlConnection("ConnectionString");
conn.Open();
SqlCommand comm = new SqlCommand("SELECT COUNT(*) FROM table_name", conn);
Int32 count = Convert.ToInt32(comm.ExecuteScalar());
if (count > 0)
{
    lblCount.Text = Convert.ToString(count.ToString()); //For example a Label
}
else
{
    lblCount.Text = "0";
}
conn.Close(); //Remember close the connection
1
Emmanuel Manzanilla González
int count = 0;    
using (new SqlConnection connection = new SqlConnection("connectionString"))
{
    sqlCommand cmd = new SqlCommand("SELECT COUNT(*) FROM table_name", connection);
    connection.Open();
    count = (int32)cmd.ExecuteScalar();
}
0
ali sriti