如何从表中检索值到变量并显示到文本框 [英] how to retrieve value from table into a variable and display to textbox

问题描述

例如：



命令：从公司选择总和（薪水），即工资总额= 10000



i希望将总和存储到变量X中，即X = 10000



我想将1000显示到文本框

< br $> b $ b

 尝试 
 {
 SqlConnection con =  new  SqlConnection（con_str）; 
 con.Open（）; 
 
 SqlCommand cmd10 =  new  SqlCommand（ 选择SUM（salary_amt）公司，con）; 
  decimal  x = cmd10.ExecuteNonQuery（）; 
 Label1.text =   Total +。ToString（）; 
 
 con.Close（）; 
} 
  catch （例外情况）
 {
 Response.Write（ex.Message）; 
} 

解决方案

解决方案1和解决方案2都为您提供了一些链接，可以引导您找到一些适用于你。



作为一个exaplanation为什么你的代码不工作 - 这个：

 cmd10.ExecuteNonQuery（ ）; 

除了查询所影响的行数之外不会返回任何内容，因此执行 NonQuery 。它通常用于更新和删除语句。要查询您期望查询结果（Select-Query）的内容，您必须使用ExecuteReader（..），如解决方案1和2的链接示例中所示。

看看这里

以下几篇文章将帮助您完成任务。



http://stackoverflow.com/questions/16565035/how-do-i- get-values-from-a-sql-database-into-textboxes-using-c [ ^ ]



http：/ /www.c-sharpcorner.com/forums /thread/150572/retrieving-data-from-database-into-textbox-in-C-Sharp-using.aspx [ ^ ]

for example :

command : select sum(Salary) from company i.e salary total=10000

i want to store the total sum into a variable X i.e X=10000

and i want to display that 1000 to textbox

try
{
SqlConnection con = new SqlConnection(con_str);
con.Open();
 
SqlCommand cmd10 = new SqlCommand("select SUM(salary_amt) company ", con);
decimal x = cmd10.ExecuteNonQuery();
Label1.text="Total"+.ToString();
 
con.Close();
}
catch (Exception ex)
{
Response.Write(ex.Message);
}

解决方案

Both Solution 1 and Solution 2 provide you with links that lead you to some example code that will work for you.

As an exaplanation why your code is not working - this:

cmd10.ExecuteNonQuery();

doesn't return anything but the number of rows affected by the query, hence "ExecuteNonQuery". It's usually used for Update- and Delete-Statements. To query something where you expect a query result (a Select-Query) you have to use ExecuteReader(..), as you can see in the linked examples of Solution 1 and 2.

Have look Here

Below are few posts, that will help you to complete your task.

http://stackoverflow.com/questions/16565035/how-do-i-get-values-from-a-sql-database-into-textboxes-using-c[^]

http://www.c-sharpcorner.com/forums/thread/150572/retrieving-data-from-database-into-textbox-in-C-Sharp-using.aspx[^]

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