具有2个条件的SQL语句中的WHERE子句

Question

I have this aspx(html) code: 我有这个aspx（html）代码：

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="SearchCustomer.aspx.cs" Inherits="WebApplication1.eyeofheaven.SearchCustomer" %>

<!DOCTYPE html>
<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" type="text/css" href="StyleSheets/SearchCustomerStyle.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap-theme.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js"></script>
<title>Search Customer</title>
</head>
<body>
<form id="form1" runat="server">
 <div class="row">
    <div class="twelve columns">
            <!-- Header-->
            <div class="container">
                <nav role="navigation" class="navbar navbar-inverse navbar-fixed-top">
                    <!-- Brand and toggle get grouped for better mobile display -->
                    <div class="navbar-header">
                        <button type="button" data-target="#navbarCollapse" data-toggle="collapse" class="navbar-toggle">
                            <span class="sr-only">Toggle navigation</span>
                            <span class="icon-bar"></span>
                            <span class="icon-bar"></span>
                            <span class="icon-bar"></span>
                        </button>
                    </div>
                    <!-- Collection of nav links, forms, and other content for toggling -->
                    <div id="navbarCollapse" class="collapse navbar-collapse">
                        <ul class="nav navbar-nav">
                            <li><a href="EyeOfHeaven.aspx">Home</a></li>
                            <li class="dropdown">
                                <a data-toggle="dropdown" class="dropdown-toggle active" href="#">Search<b class="caret"></b></a>
                                <ul role="menu" class="dropdown-menu">
                                    <li><a href="SearchCustomer.aspx">Search Form(Customer)</a></li>
                                    <li><a href="SearchVehicle.aspx">Search Form(Vehicle)</a></li>
                                </ul>
                            </li>
                        </ul>
                    </div>
                </nav>
            </div>
    </div>
</div>

<!-- Search form customer-->
<div id="searchcustomer" class="page-header">
    <h3><span class="glyphicon glyphicon-th-large"></span>Search Customer</h3>
</div>
<div class="row">
    <div class="col-md-4">
        <input type="text" runat="server" id="search" size="20" class="form-control" placeholder="Customer ID">
    </div>
    <div class="col-md-4">
        <select class="form-control" runat="server" id="Country">
            <option value="select" selected disabled>Search by Country</option>
            <option value="A:C ESTUDIO">A:C ESTUDIO</option>
            <option value="Aaron McEwen-194712">Aaron McEwen-194712</option>
            <option value="Accra">Accra</option>
            <option value="Adoany">Adoany</option>
            <option value="Aduanas">Aduanas</option>
            <option value="Alex Sanchez-259029">Alex Sanchez-259029</option>
            <option value="ALG Consulting-288078">ALG Consulting-288078</option>
            <option value="Algeria">Algeria</option>
            <option value="Algimantas Ramaskevicius">Algimantas Ramaskevicius</option>
            <option value="Allan Demeritte-233953">Allan Demeritte-233953</option>
            <option value="Althea  Gibson-223990">Althea  Gibson-223990</option>
            <option value="Alvaro Delgado-279974">Alvaro Delgado-279974</option>
            <option value="Amber Williamsen-212332">Amber Williamsen-212332</option>
            <option value="Amos Peters-217784">Amos Peters-217784</option>
            <option value="andersongordon-234453">andersongordon-234453</option>
            <option value="Andrey Bolshakov-189544">Andrey Bolshakov-189544</option>
            <option value="Angela green-220269">Angela green-220269</option>
            <option value="ANGELMILLER-179184">ANGELMILLER-179184</option>
            <option value="Angola">Angola</option>
            <option value="Anguilla">Anguilla</option>
            <option value="Anthony Knight-235064">Anthony Knight-235064</option>
            <option value="Antigua and Barbuda">Antigua and Barbuda</option>
            <option value="Anton Transport">Anton Transport</option>
            <option value="Argentina">Argentina</option>
            <option value="Armenia">Armenia</option>
            <option value="Aruba">Aruba</option>
            <option value="Australia">Australia</option>
            <option value="Austria">Austria</option>
            <option value="Bahamas">Bahamas</option>
            <option value="Bahrain">Bahrain</option>
            <option value="Bangladesh">Bangladesh</option>
            <option value="Barbados">Barbados</option>
            <option value="Belgium">Belgium</option>
            <option value="Belize">Belize</option>
            <option value="Benin">Benin</option>
            <option value="Bermuda">Bermuda</option>
        </select>
    </div>  

    <div class="col-md-4">
        <select class="form-control" runat="server" id="Currency">
            <option value="selected" selected disabled>Search by Currency</option>
            <option value="AUD">AUD Australian Dollar</option>
            <option value="EUR">EUR</option>
            <option value="GBP">GBP United Kingdom Pounds</option>
            <option value="JPY">JPY Japan Yen</option>
            <option value="NZD">NZD New Zealand Dollar</option>
        </select>
    </div>
</div>
<div class="row">
    <div class="col-md-4">
<button type="button" runat="server" onserverclick="Button1_Click" id="searchinfo" class="btn btn-primary"><span class="glyphicon glyphicon-search"></span> Search Info</button>
    </div>
</div>

<!-- Information Table-->
<div id="gridview">
    <asp:GridView runat="Server" id="data" CssClass="table table-striped table-bordered table-responsive">
    </asp:GridView>
</div>

</form>
</body>
</html>

And its aspx.cs code behind: 它的aspx.cs代码背后：

using MSSQLConnector;
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace WebApplication1.eyeofheaven
{
    public partial class SearchCustomer : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
        }
        protected void Button1_Click(object sender, EventArgs e)
        {

            MSConnector connector = new MSConnector();
            connector.ConnectionString = "SERVER=xbetasql,52292;UID=username;Password=secret;DATABASE=ATDBSQL;";

            string customer = (this.search.Value);
            string country = (this.Country.Value);
            string idcurrency = (this.Currency.Value);
            string query = null;

            if (country != "select")
            {
                query = "select * from customer where country = '" + country + "'";
            }
            else if (idcurrency != "selected")
            {
                query = "select * from customer where idcurrency = '" + idcurrency + "'";
            }
            else if ((country != "select") && (idcurrency != "selected"))
            {
                query = "select * from customer where country = '" + country + "select * from customer where idcurrency = '" + idcurrency + "'";
            }
            else if (customer == customer)
            {
                query = "select * from customer where idcustomer = '" + customer + "'";
            }
            else if (customer == "")
            {
                Response.Write("<script>alert('No Id Inputted, Data Not Found.')</script>");
            }
            DataSet selectedData = connector.ExecuteQuery(query);
            DataTable dt = selectedData.Tables[0];
            data.DataSource = dt;
            data.DataBind();
        }
    }
}

I have a problem about the condition, I want to make my select tag to display the data when I select the two option, ex: I select "Aduanas" from country and then select another option "USD" from Currency. 我有一个关于条件的问题，当我选择两个选项时，我想让我的选择标签显示数据，例如：我从国家选择“Aduanas”，然后从货币中选择另一个选项“USD”。 But it will only get the data of the first select tag(Country) that I selected, my condition does not read and get the data of the two values of the Country and Currency. 但它只会获取我选择的第一个选择标记（国家）的数据，我的条件不会读取并获取国家和货币的两个值的数据。 I'm new to c# programming and ms sql and I'm learning the syntax and functions of it. 我是c＃编程和ms sql的新手，我正在学习它的语法和功能。

My condition about the country and currency (select tag) below: 我的国家和货币（选择标签）的条件如下：

else if ((country != "select") && (idcurrency != "selected"))
{
    query = "select * from customer where country = '" + country + "select * from customer where idcurrency = '" + idcurrency + "'";
}

Answer 1

There is a syntax error in your SQL; SQL中存在语法错误; instead of: 代替：

query = "select * from customer where country = '" + country + "select * from customer where idcurrency = '" + idcurrency + "'";

it should be like the following: 它应该如下：

query = "select * from customer where country = '" + country + "' AND idcurrency = '" + idcurrency + "'";

Hope this may help. 希望这可能有所帮助。

Answer 2

Based on your current code, the first if block below will always be executed when you select a country, whether you choose a currency or not 根据您当前的代码，当您选择国家/地区时，无论您是否选择货币，下面的第一个if块将始终执行

if (country != "select")
{
    query = "select * from customer where country = '" + country + "'";
}

You need to check the selected currency inside the first if block as well. 您还需要检查第一个if块内的所选货币。 I've also fixed the incorrect SQL syntax. 我还修复了错误的SQL语法。

if (country != "select")
{
    if (idcurrency != "selected")
    {
        query = "select * from customer where country = '" + country + "' and idcurrency = '" + idcurrency + "'";
    }
    else
    {
        query = "select * from customer where country = '" + country + "'";
    }
}

具有2个条件的SQL语句中的WHERE子句

问题描述

2 个解决方案

解决方案1
4 2015-06-09 03:22:08

解决方案2
4 已采纳 2015-06-09 03:26:45

具有2个条件的SQL语句中的WHERE子句

问题描述

2 个解决方案

解决方案1 4 2015-06-09 03:22:08

解决方案2 4 已采纳 2015-06-09 03:26:45

解决方案1
4 2015-06-09 03:22:08

解决方案2
4 已采纳 2015-06-09 03:26:45