textbox 和lable换行保存和显示

<asp:TextBox ID="TextBox1" runat="server" TextMode="MultiLine"></asp:TextBox>
<asp:Button ID="Button1" runat="server" onclick="Button1_Click" Text="Button" />
<br />
<asp:Label ID="Label2" runat="server" Text="Label"></asp:Label>

string txt = TextBox1.Text;
StringBuilder strSql = new StringBuilder();
strSql.Append("insert into text_table ");
strSql.Append("values(");
strSql.Append("'" + "',''" + ",''" + ",''" + ",''" + ",'" + "','" + TextBox1.Text + "'");
strSql.Append(")");
int countcj = DbHelperSQL.ExecuteSql(strSql.ToString());

DataSet ds = DbHelperSQL.Query("select * from text_table where a='3'");
string strtext = ds.Tables[0].Rows[0]["bz"].ToString();
TextBox1.Text = strtext;
Label2.Text = TextBox1.Text.Replace("\r\n", " <br>");