比较用户注册时查询SQL中“用户名”与输入是否一致 问题:如题;目的:设计一用户注册页面,在代码内实现查询比较,避免重复注册 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 select count(*) from t_user where t_user.name='name' 页面TextBox2数据库User表Name项代码if(***){ }问题就在于***如何操作select 出来后,返回的是什么呢? string strConn = "";//连接你自己写吧string strSQL = "Select COUNT(*) From User Where Name = '" + TextBox2.Text + "'";System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection(strConn);conn.Open();System.Data.SqlClient.SqlCommand cmd = new System.Data.SqlClient.SqlCommand(strSQL);int count = Convert.ToInt32(cmd.ExecuteScalar());if (count > 0){ //已经存在该用户}conn.Close(); sqlConnection1.Open();string sqlStr="SELECT * FROM XX"; SqlCommand cmd=new SqlCommand(sqlStr,sqlConnection1);SqlDataReader dataReader= cmd.ExecuteReader();while(dataReader.Read()){string RegID=dataReader["ID"].ToString().Replace(" ","");ifRegBox.Text.ToString().Replace(" ","")==RegID){MessageBox.show("小样,请别重复注册");}} ```漏了个括号```sqlConnection1.Open();string sqlStr="SELECT * FROM XX"; SqlCommand cmd=new SqlCommand(sqlStr,sqlConnection1);SqlDataReader dataReader= cmd.ExecuteReader();while(dataReader.Read()){string RegID=dataReader["ID"].ToString().Replace(" ","");if(RegBox.Text.ToString().Replace(" ","")==RegID){MessageBox.show("小样,请别重复注册");} Snowdust(雪尘) 你怎么老和我抢分 SqlConnection con = new SqlConnection(); con.ConnectionString = System.Configuration.ConfigurationSettings.AppSettings["DSN"]; con.Open(); string strSql = "select * from GustReg.UserName = '" + tbUserName.Text + "'"; SqlCommand com = new SqlCommand(strSql, con); SqlDataReader dr = com.ExecuteReader(); bool bExist = false; while (dr.Read()) { bExist = true; Session["AdmName"] = dr.GetString(0); } if (bExist) { Response.Write("<script language='javascript'>alert('用户名已存在,请更换用户名注册')</script>"); } VB.net 怎么改成 C#.net unsafe代码如何调试啊 请教一个C#控制Excel的问题 [求助]怎么将单选按钮和数据库进行绑定 C#读dat文件! C# 加密!!! C#哪个版本的IDE比较好用? 基础问题,给分题 网页首次登录的指引操作如何处理 弄了一天了也没搞定...Asp.NET下:未能获取此实现的 CryptoAPI 加密服务提供程序(CSP)。 关于正则表达式的问题,大侠们帮我看看吧 请问在VS2005中怎样浏览XML数据库
数据库User表Name项
代码if(***){ }
问题就在于***如何操作select 出来后,返回的是什么呢?
string strSQL = "Select COUNT(*) From User Where Name = '" + TextBox2.Text + "'";
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection(strConn);
conn.Open();
System.Data.SqlClient.SqlCommand cmd = new System.Data.SqlClient.SqlCommand(strSQL);
int count = Convert.ToInt32(cmd.ExecuteScalar());
if (count > 0)
{
//已经存在该用户
}
conn.Close();
string sqlStr="SELECT * FROM XX";
SqlCommand cmd=new SqlCommand(sqlStr,sqlConnection1);
SqlDataReader dataReader= cmd.ExecuteReader();
while(dataReader.Read())
{
string RegID=dataReader["ID"].ToString().Replace(" ","");
ifRegBox.Text.ToString().Replace(" ","")==RegID)
{
MessageBox.show("小样,请别重复注册");
}}
sqlConnection1.Open();
string sqlStr="SELECT * FROM XX";
SqlCommand cmd=new SqlCommand(sqlStr,sqlConnection1);
SqlDataReader dataReader= cmd.ExecuteReader();
while(dataReader.Read())
{
string RegID=dataReader["ID"].ToString().Replace(" ","");
if(RegBox.Text.ToString().Replace(" ","")==RegID)
{
MessageBox.show("小样,请别重复注册");
}
con.ConnectionString = System.Configuration.ConfigurationSettings.AppSettings["DSN"];
con.Open(); string strSql = "select * from GustReg.UserName = '" + tbUserName.Text + "'";
SqlCommand com = new SqlCommand(strSql, con);
SqlDataReader dr = com.ExecuteReader();
bool bExist = false;
while (dr.Read())
{
bExist = true;
Session["AdmName"] = dr.GetString(0);
}
if (bExist)
{
Response.Write("<script language='javascript'>alert('用户名已存在,请更换用户名注册')</script>");
}