SQL異常未處理'='附近的語法不正確？

Question

這是我的搜索按鈕：

private void btnSearch_Click(object sender, EventArgs e)
    {
        string RegNo = txtRegNo.Text;
        txtFname.Text = dba.ReturnStudentData("RegNo", "Student", RegNo, "PhoneNo");
        txtLname.Text = dba.ReturnStudentData("RegNo", "Student", RegNo, "Lname");
        txtPhoneNo.Text = dba.ReturnStudentData("RegNo", "Student", RegNo, "PhoneNo");

    }

這是我的DB_Access：

public string ReturnStudentData(string Primary_key, string Table_Name, string RegNo, string Column)
    {
        string temp = "";
        if (conn.State.ToString() == "Closed")
        {
            conn.Open();
        }
        SqlCommand newCmd = conn.CreateCommand();
        newCmd.CommandType = CommandType.Text;
        newCmd.CommandText="SELECT"+Column+"FROM"+Table_Name+"WHERE"+Primary_key+"="+RegNo+"";
        SqlDataReader dr = newCmd.ExecuteReader(); **// here i got error**

        while(dr.Read())
        {
            temp = dr[Column].ToString();
        }
        dr.Close();
        conn.Close();
        return temp;
    }

這是我上面的代碼，當我搜索數據庫放置的主數時，我出錯了..誰能幫我..

Answer 1

首先，您應該在sql命令中添加空格

newCmd.CommandText="SELECT "+Column+" FROM "+Table_Name+" WHERE "+Primary_key+"="+RegNo+"";

否則你會得到類似的東西：

SELECTcolumnt1,column2FROMmyTableWHEREKey=123

代替：

SELECT columnt1,column2 FROM myTable WHERE Key=123

其次，打印newCmd.CommandText以查看最終查詢是什么。