从数据表C#计数值 [英] Count Value from datatable C#
本文介绍了从数据表C#计数值的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我需要帮助,
我有以下数据表
NO |项目|价格|
------------------
1 |书| 15 |
2 |笔| 10 |
------------------
i想从列中获取字符串值价格10 + 15 = '25'
i need help,
i have datatable like below
NO | Item |Price |
------------------
1 | Book | 15 |
2 | Pen | 10 |
------------------
i want get string value from column price 10 + 15 = '25'
推荐答案
使用 SQL SUM ()功能 [ ^ ]。
请查看它是否解决了你的问题。
Hi,
Please see if it solves your question.
The COUNT() function returns the number of rows that matches a specified criteria.
SQL COUNT(column_name) Syntax
The COUNT(column_name) function returns the number of values (NULL values will not be counted) of the specified column:
SELECT COUNT(column_name) FROM table_name;
The SUM() Function
The SUM() function returns the total sum of a numeric column.
SQL SUM() Syntax
SELECT SUM(column_name) FROM table_name;
using System;
using System.Data;
using System.Data.SqlClient;
using System.Windows.Forms;
namespace WindowsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
string connetionString = null;
SqlConnection connection ;
SqlCommand command ;
SqlDataAdapter adapter = new SqlDataAdapter();
DataSet ds = new DataSet();
string sql = null;
connetionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password";
sql = "Your SQL Statement Here";
connection = new SqlConnection(connetionString);
try
{
connection.Open();
command = new SqlCommand(sql, connection);
adapter.SelectCommand = command;
adapter.Fill(ds, "SQL Temp Table");
adapter.Dispose();
command.Dispose();
connection.Close();
MessageBox.Show ("Number of row(s) - " + ds.Tables[0].Rows.Count);
}
catch (Exception ex)
{
MessageBox.Show("Can not open connection ! ");
}
}
}
}
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