从我的文本框将值传递给SQL查询参数 [英] Passing value to SQL query parameter from my textbox

问题描述

我正在使用以下代码连接到我的数据库.

Hi,
I am using following code to connect to my database.

<pre lang="vb"> Dim conStr As String = "Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\dbTest.mdf;Integrated Security=True;User Instance=True"
     Dim sqlQry As String = "SELECT * FROM [tblTest] WHERE ([Name] = @Name)"
       Dim dAdt As New SqlDataAdapter(sqlQry, conStr)
    Dim dSet As New DataSet()

然后用
填充适配器

Then filling adapter with

<pre lang="vb">dAdt.Fill(dSet, "tblTest")

然后我可以按照自己想要的方式使用数据.

我的问题是:
如何通过文本框传递用户将给出的参数值.

and then I can use the data the way I want.

My question is:
How to pass the value of parameter that user will give through a text box.

Dim sqlQry As String = "SELECT * FROM [tblTest] WHERE ([Name] = @Name)

"

我的意思是如何将参数值传递给我的查询?
请修改我的代码以告诉我该怎么做.
非常感谢.

"

I mean how to pass the parameter value to my query?
Please modify my code to tell me how to do it.
Thanks a lot.

推荐答案

有两种方法:

解决方案1:

There are two ways to do so :

Solution 1 :

Dim sqlQry As String = "SELECT * FROM [tblTest] WHERE [Name] = " + textBox1.text

解决方案2:

Solution 2 :

Dim sqlQry As String = "SELECT * FROM [tblTest] WHERE [Name] = @Name"

Dim command As New SqlCommand(sqlQry, connection)

'' Add Name parameter for WHERE clause.
command.Parameters.Add("@Name", SqlDbType.Varchar, 20) -- 20 Refers to the size
command.Parameters("@Name").Value = textBox1.Text

希望这会有所帮助.
一切顺利.

Hope this helps.
All the best.

请参阅此处: http://vbnetsample.blogspot.com/2007/10/using-sqlparameter-class.html [ ^ ]

使用参数(这正是您应该做的)，您应该定义一个SqlCommand对象分别使用该命令作为您的数据适配器.因此整个代码可能类似于:

When you use parameters (and that''s exactly what you should do) you should define a SqlCommand object separately and use that command for your data adapter. So the whole code could look something like:

Dim conStr As String = "Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\dbTest.mdf;Integrated Security=True;User Instance=True"
Dim sqlQry As String = "SELECT * FROM [tblTest] WHERE ([Name] = @Name)"
Dim dAdt As New System.Data.SqlClient.SqlDataAdapter()
Dim dSet As New DataSet()
Dim queryCommand As New System.Data.SqlClient.SqlCommand()
Dim queryConnection As New System.Data.SqlClient.SqlConnection()

queryConnection.ConnectionString = conStr
queryConnection.Open()
queryCommand.Connection = queryConnection
queryCommand.CommandText = sqlQry
queryCommand.Parameters.AddWithValue("@Name", textBox1.Text)
dAdt.SelectCommand = queryCommand
dAdt.Fill(dSet)
queryConnection.Close()

请记住将textBox1.Text替换为实际的文本框对象.

另外，打开连接，执行填充等也应包含在适当的try..catch块

Remember to replace textBox1.Text with your actual text box object.

Also opening the connection, executing the fill etc should be enclosed to proper try..catch block

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