vb.net数据库编程(04):一个SQLserver修改记录的简单例子。
同样,修改只是把结果返回数据库,不会显示。 因此,用一个判断来提示用户,修改是成功或者是失败,这样用户才好进行下一步。 这个例子,更简单,因为我们减少了再一次查询结果的代码。 因为修改中用了SQlcommand中的非查询方法。所以没有用到DataAdapter和D
同样,修改只是把结果返回数据库,不会显示。
因此,用一个判断来提示用户,修改是成功或者是失败,这样用户才好进行下一步。
这个例子,更简单,因为我们减少了再一次查询结果的代码。
因为修改中用了SQlcommand中的非查询方法。所以没有用到DataAdapter和DataSet。
Imports System.Data.SqlClient Public Class Form1 Dim cn As SqlConnection Dim cm As SqlCommand Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click Try cn = New SqlConnection("Data Source=127.0.0.1;Initial Catalog=Sales;Integrated Security=False;User ID=sa;Password=123456;") cn.Open() '此句不能少 cm = New SqlCommand(TextBox1.Text, cn) cm.ExecuteNonQuery() cn.Close() MessageBox.Show("操作成功") Catch ex As Exception MessageBox.Show("操作失败") End Try End Sub End Class
结果如下:
这个例子减少了回显和修改SQl语句在代码中的集成,为了就是看清执行修改时不同的实现。
SQlcommand的不同。

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