NET 增加修改删除查找

配置数据源的时候选高级，勾上“生成insert,update,delete”，这样就自动有修改，删除功能，然后只要写增加和查找代码而已

 

using System.Data.SqlClient;

 

public partial class _Default : System.Web.UI.Page
{
    SqlConnection conn = new SqlConnection("data source=localhost;user id=sa;pwd=;initial catalog=c#;");

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            bind();
        }       
    }
    public void bind()
    {
        SqlDataAdapter myda = new SqlDataAdapter("select * from users", conn);
        DataSet myds = new DataSet();
        conn.Open();
        myda.Fill(myds, "users");
        GridView1.DataSource = myds;
        GridView1.DataKeyNames = new string[] { "id" };//主键
        GridView1.DataBind();
        conn.Close();
    }
    protected void Button2_Click(object sender, EventArgs e)   //增加
    {
        conn.Open();
        SqlCommand cmd = new SqlCommand("insert into users(username,password) values('"+TextBox2.Text+"','"+TextBox3.Text+"')",conn);
        cmd.ExecuteNonQuery();
        conn.Close();
        bind();
    }
    protected void Button1_Click(object sender, EventArgs e)   //查找
    {
        string sqlstr = "";
        if (TextBox1.Text == "")
        {
            sqlstr = "select * from users ";
        }
        else
        {
            sqlstr = "select * from users where username='" + TextBox1.Text + "'";
        }
        SqlDataAdapter myda = new SqlDataAdapter(sqlstr, conn);
        DataSet myds = new DataSet();
        conn.Open();
        myda.Fill(myds, "users");
        GridView1.DataSource = myds;
        GridView1.DataKeyNames = new string[] { "id" };//主键
        GridView1.DataBind();
    }
    protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)   //删除
    {
        SqlCommand cmd = new SqlCommand("delete from users where id='" + GridView1.DataKeys[e.RowIndex].Value.ToString() + "'", conn);
        conn.Open();
        cmd.ExecuteNonQuery();
        conn.Close();
        bind();
    }
    protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)   //修改
    {
        string sqlstr = "update users set username='"
            + ((TextBox)(GridView1.Rows[e.RowIndex].Cells[1].Controls[0])).Text.ToString().Trim() + "' where id='"
            + GridView1.DataKeys[e.RowIndex].Value.ToString() + "'";
        SqlCommand cmd = new SqlCommand();
        cmd = new SqlCommand(sqlstr, conn);
        conn.Open();
        cmd.ExecuteNonQuery();
        conn.Close();
        GridView1.EditIndex = -1;
        bind();
    }
    protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)   //修改
    {
        GridView1.EditIndex = e.NewEditIndex;
        bind();
    }
}