asp.net用数据库进行信息查询，为什么会出现列名无效？以下代码中第一个if可以执行为什么第二个if就不行了

？“姓名”“学号”都在一个表里，代码也没差，为什如果用“姓名”查询就会“列名无效”？请教各位，谢谢……


if (this.RadioButton1.Checked == true)
        {
            SqlCommand cmd = new SqlCommand();
            DataSet ds = new DataSet();
            SqlDataAdapter sda = new SqlDataAdapter("select*from chlesson where 学号=" + this.TextBox1.Text + "", con);
            sda.Fill(ds, "chlesson");
            this.GridView1.DataSource = ds;
            this.GridView1.DataBind();
        }
       
            if (this.RadioButton2.Checked == true)
            {
                SqlCommand cmd = new SqlCommand();
                DataSet ds = new DataSet();
                SqlDataAdapter sda = new SqlDataAdapter("select*from chlesson where 姓名=" + this.TextBox2.Text + "", con);
                sda.Fill(ds, "chlesson");
                this.GridView1.DataSource = ds;
                this.GridView1.DataBind();
            }