private void label4_Click(object sender, EventArgs e)
{
user_history form = new user_history();
form.Show();
this.Dispose();
}
private void button3_Click(object sender, EventArgs e)
{
//界面替换 点击查询历史按钮 进入历史界面
user_history form = new user_history();
form.Show();
this.Dispose();
}