如何将数据从数据库传输到文本框？

本文介绍了如何将数据从数据库传输到文本框？的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 29岁程序员，3月因学历无情被辞！ 我不能将数据从数据库传输到文本框。请帮帮我。I can not do transferring data to textboxes from database. Help me please.="c#">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 MySql.Data.MySqlClient;namespace WindowsFormsApplication1{ public partial class Form4 : Form { public Form1 frm1; public Form2 frm2; public Form3 frm3; public Form4 frm4; public Form4() { InitializeComponent(); } private void Form4_Load(object sender, EventArgs e) { try { int a = 0; string wanted, id, username, password, email, secureword, name, surname, age, gender, country; MySqlConnection conn = new MySqlConnection("server=localhost;database=naperva;user=root;password="); MySqlCommand cmd = new MySqlCommand("SELECT * FROM users WHERE id, username, password, email, secureword, name, surname, age, gender, country", conn); MySqlDataReader read = null; conn.Open(); read = cmd.ExecuteReader(); wanted = frm1.loginUsername_txt.Text; while (read.Read()) { id = read["id"].ToString(); username = read["username"].ToString(); password = read["password"].ToString(); email = read["email"].ToString(); secureword = read["secureword"].ToString(); name = read["name"].ToString(); surname = read["surname"].ToString(); age = read["age"].ToString(); gender = read["gender"].ToString(); country = read["country"].ToString(); if (wanted == username) { id = myprofileID_txt.Text; username = myprofileUsername_txt.Text; password = myprofilePassword_txt.Text; email = myprofileEmail_txt.Text; secureword = myprofileSecureWord_Txt.Text; name = myprofileName_txt.Text; surname = myprofileSurname_txt.Text; gender = myprofileGender_comboBox.Text; age = myprofileAge_txt.Text; country = myprofileCountry_txt.Text; a = 1; } if (a != 1) { MessageBox.Show("Not found"); read.Close(); conn.Close(); } } } catch (Exception) { MessageBox.Show("DATABASE ERROR"); } } }}推荐答案myprofileCountry_txt.Text = country;read = cmd.ExecuteReader(); 共有4种表格。全部互连。There are a total of 4 forms. All interconnected.public Form1() { InitializeComponent(); frm2 = new Form2(); frm3 = new Form3(); frm4 = new Form4(); frm2.frm1 = this; frm3.frm1 = this; frm4.frm1 = this; } 我用各种形式写的相同：I wrote the same in all forms:public Form1 frm1; public Form2 frm2; public Form3 frm3; public Form4 frm4; 有报名表和将成员添加到数据库表单。单击一个按钮打开Form4（我的个人资料）。在Form4中，在写入数据时注册。对不起，发给我不明白的代码。抱歉我的英语：）There are entry form and add members to the database form. When the click a button open the Form4(My Profile). In the Form4, sign up, while writing data. Sorry, send you the code I did not understand. And sorry for my English :)MySqlCommand cmd = new MySqlCommand("SELECT * FROM users WHERE id, username, password, email, secureword, name, surname, age, gender, country", conn); totowanted = frm1.loginUsername_txt.Text;MySqlCommand cmd = new MySqlCommand("SELECT * FROM users WHERE username ='"+wanted +"'", conn); 你最好检查一下sql的语法 [ ^ ]并且还将字符串与sql语句连接不安全，它将打开sql注入atacks。我会使用参数，如果它只是用于验证用户是否存在;示例代码：you better check the sql where syntax [^] and also concatenating strings not safe way with sql statements, it will open sql injection atacks. I would use parameters and if it it is only for validating user exist or not; sample code:public bool ValidateUser(string username, string password){ int count = 0; string query = "SELECT count(*) FROM users WHERE username = @user AND password = @pass"; using(MySqlConnection conn = new MySqlConnection("server=localhost;database=naperva;user=root;password=")) using (MySqlCommand cmd = new MySqlCommand(query, conn)) { cmd.Parameters.Add(new MySqlParameter("@user", username)); cmd.Parameters.Add(new MySqlParameter("@pass ", password)); connector.Open(); count = int.Parse(cmd.ExecuteScalar().ToString()); } return count > 0;} 这篇关于如何将数据从数据库传输到文本框？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！ 上岸，阿里云！