数据写不进去access表中，怎么改呢？

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.OleDb;

namespace 专科医院门诊系统_眼科_
{

public partial class 挂号界面 : Form
{

    OleDbConnection con = new OleDbConnection();
    string str = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=E:\design\vc\project\专科医院门诊系统（眼科）\db1.accdb";
    public 挂号界面()
    {
        InitializeComponent();
        con.ConnectionString = str;
        button1.Click += new EventHandler(button1_Click);
        button2.Click += new EventHandler(button2_Click);
        button3.Click += new EventHandler(button3_Click);
    }
    private void textBox1_TextChanged(object sender, EventArgs e)
    {

    }

    private void textBox2_TextChanged(object sender, EventArgs e)
    {

    }

    private void textBox3_TextChanged(object sender, EventArgs e)
    {

    }

    private void textBox4_TextChanged(object sender, EventArgs e)
    {

    }
    private void textBox5_TextChanged(object sender, EventArgs e)
    {

    }
    private void textBox6_TextChanged(object sender, EventArgs e)
    {

    }   
    private void button1_Click(object sender, EventArgs e)
    {
        挂号缴费选择界面 frm = new 挂号缴费选择界面();
        frm.Show();
        Hide();
    }

    private void button2_Click(object sender, EventArgs e)
    {
        if (textBox1.Text != "" && textBox2.Text != ""&& textBox3.Text != ""&& textBox4.Text != ""&& textBox5.Text != ""&& textBox6.Text != "")
        {
        string a = textBox1 .Text ;
        string b = textBox2 .Text ;
        string c = textBox3 .Text ;
        string d = textBox4 .Text ;
        string f = textBox5 .Text ;
        string g = textBox6 .Text ;
        OleDbCommand cmd = new OleDbCommand(@"insert into [patient](ID,名字,年龄,性别,电话号码,科室)  values(" + a + ",'" + b + "'," + c + ",'" + d + "',"+ f + ",'"+ g + "')");
        con.Open();
        cmd.Connection = con;
        cmd.ExecuteNonQuery();
        con.Close();
        MessageBox.Show("挂号成功！");
        }
        else
        {

         MessageBox .Show ("请输入完整的挂号信息");
        }



        textBox1.Text = textBox2.Text = textBox3.Text = textBox4.Text = textBox5.Text = textBox6.Text = string.Empty;
    }
    private void button3_Click(object sender, EventArgs e)
    {
        textBox1.Text = textBox2.Text = textBox3.Text = textBox4.Text = textBox5.Text =textBox6.Text = string.Empty;
    }
    private void 挂号界面_Load(object sender, EventArgs e)
    {

    }
}

}

采纳，将代码发网盘，可以帮你。

挂号成功或者请输入完整的挂号信息，会跳出来，就是写不进去 access，里面是空的