在数据库中插入文本框值

Question

我使用以下代码将 TextBox 值保存到数据库中。但是，当我插入该值时，它将保存在新行中。如何将其保存到同一行？

private void button1_Click(object sender, EventArgs e)
{
    string pass = textBox1.Text;
    sql = new SqlConnection(@"Data Source=PC-PC\PC;Initial Catalog=P3;Integrated Security=True");
    SqlCommand cmd = new SqlCommand();
    cmd.Connection = sql;
    cmd.CommandText = ("Insert [MyTable] ([MyColumn]) Values (@pass)");
    cmd.Parameters.AddWithValue("@pass", pass);
    sql.Open();
    cmd.ExecuteNonQuery();
    sql.Close();
}

Answer 1

使用更新命令代替插入。

cmd.CommandText = "update YourTable set FieldName = YourValue where KeyField = YourKeyValue"

Answer 2

您需要使用 UPDATE 而不是 INSERT，类似于：

UPDATE yourTable
SET yourColumn = newValue
WHERE (your criteria needs to go here) ID = recordId

您需要为记录创建 UPDATE 语句。如果您打算全部更新，那么您的声明将是：

UPDATE yourTable
SET yourColumn = newValue

否则，您将需要告诉它要更新哪些记录

UPDATE yourTable
SET yourColumn = newValue
WHERE ID = yourID

private void button1_Click(object sender, EventArgs e)
{
    string pass = textBox1.Text;
    sql = new SqlConnection(@"Data Source=PC-PC\PC;Initial Catalog=P3;Integrated Security=True");
    SqlCommand cmd = new SqlCommand();
    cmd.Connection = sql;
    cmd.CommandText = "UPDATE MyTable SET MyColumn = @pass WHERE id=@id"
    cmd.Parameters.AddWithValue("@pass", pass);
    cmd.Parameters.AddWithValue("@id", 1);
    sql.Open();
    cmd.ExecuteNonQuery();
    sql.Close();
}

这是一个网站，其中包含一些使用 ADO.NET 进行说明的示例：

Simple ADO.NET Database Read, Insert, Update and Delete using C#

How to use UPDATE in ado net