这个是我第一次按 button1按钮 时 显示的数据 这是我再次按 button1 时 显示的信息,可以发现 我第二次按 button1 时 显示的数据 有重复
我想知道 怎样可以 在按 第二次 按钮时 可以将 第一次 的表格信息 删除掉,再显示第二次的信息。我的代码如下:private DataSet ds = new DataSet();
private SqlConnection conn = null;
private SqlDataAdapter da = null;
private const string DRIVER = "server=192.168.0.2;database=StudentMISDB;uid=sa;pwd=123456";
private const string sql_select = "select * from T_Users"; public Form1()
{
InitializeComponent();
} private void button1_Click(object sender, EventArgs e)
{
conn = new SqlConnection(DRIVER);
da = new SqlDataAdapter(sql_select, conn);
da.Fill(ds, "table");
this.dataGridView1.DataSource = ds.Tables["table"].DefaultView;
}
private DataSet ds ; //这里定义
private SqlConnection conn = null;
private SqlDataAdapter da = null;
private const string DRIVER = "server=192.168.0.2;database=StudentMISDB;uid=sa;pwd=123456";
private const string sql_select = "select * from T_Users"; public Form1()
{
InitializeComponent();
} private void button1_Click(object sender, EventArgs e)
{
conn = new SqlConnection(DRIVER);
da = new SqlDataAdapter(sql_select, conn);
ds=new DataSet(); //在这里实例化
da.Fill(ds, "table");
// this.dataGridView1.DataSource=null; //这句不要也行
this.dataGridView1.DataSource = ds.Tables["table"].DefaultView;
}
可以用 ds.Reset(); 应该 就不会有重复的出现了````
private void button1_Click(object sender, EventArgs e)
{
conn = new SqlConnection(DRIVER);
da = new SqlDataAdapter(sql_select, conn);
da.Fill(ds, "table");
this.dataGridView1.DataSource = ds.Tables["table"].DefaultView;
}
da.Fill(ds, "table");这一句有问题,
前面应该加上一句,ds.Table["table"].Rows.Clears();
一个Fill动作会在对应DataTable中加入新记录,所以之前要清除DataTable里老的数据
private SqlConnection conn = null;
private SqlDataAdapter da = null;
private const string DRIVER = "server=192.168.0.2;database=StudentMISDB;uid=sa;pwd=123456";
private const string sql_select = "select * from T_Users"; public Form1()
{
InitializeComponent();
} private void button1_Click(object sender, EventArgs e)
{
ds.clear();
conn = new SqlConnection(DRIVER);
da = new SqlDataAdapter(sql_select, conn);
da.Fill(ds, "table");
this.dataGridView1.DataSource = ds.Tables["table"].DefaultView;
}
之前清空ds