标签: foreach

这是我的代码

$query = mysql_query("SELECT * FROM accommodation_vacancies WHERE accommodation_id = '$accom'");
$results = mysql_fetch_array($query);
if($query === FALSE) {
    die(mysql_error()); 
} else {
    print_r($results);
    foreach ($results as $result) {
        echo $result['start_date']; echo "<br/>";
    }           
}

这是我的输出

通过使用print_rcommant我可以看到变量$results正常工作,查询也正常工作,我想我在foreach循环上有错误.谢谢.

$pass = array();

foreach ($var as $index) 
{
    if($index['Data']['Show'] == false)
        continue;

    $pass[] = $index;
}

echo json_encode($pass);

我需要知道如何以更简化和更快的速度获得相同的结果.

所以,我有一个简单的代码部分,我需要处理一个对象数组,并知道数组中availability.prop1的某个对象是否等于true并返回true它,或者如果等于false,则返回false.这是一个非常简单的案例,我知道,但由于某些原因,我无法弄清楚我的堕落在哪里......

我对输出的期望是什么isSomeProp1EqualToTrue = true,因为数组中的第二个对象data具有正值prop1(true)

const data = [
 {prop1: false, {prop2: 'someValue'},
 {prop1: true, {prop2: 'someValue'},
 {prop1: false, {prop2: 'someValue'}
]

const isSomeProp1EqualToTrue = data.forEach(availability => {
  if (availability.prop1 === true) {
    return true
  }

  return false
})

// expected: isSomeProp1EqualToTrue = true (that's what I nedd)
// current: isSomeProp1EqualToTrue = undefined (wrong)

最近的更新导致我的代码中出现严重的性能损失.通过使用剖析器,我发现损失是由使用Linq的一条线引起的.我做了一些测试,发现Linq慢得多foreach.

        List<int> numbers = new List<int>();
        for (int i = 0; i < 1000; ++i)
            numbers.Add(i);
        var stopWatch = new Stopwatch();

        {
            int total = 0;
            for (int i = 0; i < 1000; ++i)
                total += i;
        }
        stopWatch.Start();
        for (int j = 0; j < 1000000; ++j)
        {
            int total = 0;
            for (int i = 0; i < 1000; ++i)
                total += i;
        }
        stopWatch.Stop();
        Console.WriteLine("Benchmark run time: {0}", stopWatch.ElapsedMilliseconds);

        {
            int total = 0; …

请查看以下代码

using System.Collections.Generic;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            List<Employee> employeeCollection = new List<Employee>();
            for (int i = 1; i < 10; i++) employeeCollection.Add(new Employee {
                EmployeeID = i, 
                EmployeeName = string.Concat("Employee", i),
                Email = string.Concat("Email", i) });


            //loop thru every record
            foreach (Employee e in employeeCollection)
            {
                SendEMail(e);
            }
        }

        private static void SendEMail(Employee employee)
        {
            // do something
        }        

    }


    class Employee
    {
        public int EmployeeID { get; set; }
        public string EmployeeName …