我是ASP.NET MVC的新手,现在通过阅读asp.net中给出的教程从零开始学习.我的问题可能太简单了,但我找不到答案.为了快速回复,我在这里问.
// GET: /Movie/Edit/5
public ActionResult Edit(int id = 0)
{
Movie movie = db.Movies.Find(id);
if (movie == null)
{
return HttpNotFound();
}
return View(movie);
}
//
// POST: /Movie/Edit/5
[HttpPost]
public ActionResult Edit(Movie movie)
{
if (ModelState.IsValid)
{
db.Entry(movie).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Index");
}
return View(movie);
}
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//
// GET: /Movie/Delete/5
public ActionResult Delete(int id = 0)
{
Movie movie = db.Movies.Find(id);
if (movie == null)
{
return HttpNotFound();
}
return View(movie);
}
//
// …Run Code Online (Sandbox Code Playgroud) // other usings are removed for the sake of brevity
using MvcMovie.Models;
namespace MvcMovie.Controllers
{
public class MoviesController : Controller
{
private MoviewDBContext db = new MoviewDBContext();
public ActionResult SearchIndex(string searchString)
{
var movies = db.Movies.Select(x => x);
if (!string.IsNullOrEmpty(searchString))
movies = movies.Where(x => x.Title.Contains(searchString));
return View(movies);
}
}
}
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// SearhcIndex.cshtml
@model IEnumerable<MvcMovie.Models.Movie>
@using (Html.BeginForm())
{
<p>
Title: @Html.TextBox("searchString")
<br />
<input type="submit" value="Filter" />
</p>
}
<table>
<tr>
<th>
@Html.DisplayNameFor(model => model.Title)
</th>
</tr>
@foreach (var …Run Code Online (Sandbox Code Playgroud) 我是一个新手C#学习者,并构建一个系统,从一组有序的问题生成问题表.每个问题表都有30个问题从问题集中随机选择.每个问题表由一个整数唯一标识,该整数用作种子值.
由于我不知道随机生成器如何工作的内部细节,我想知道无论.NET版本如何,使用相同种子的n-th调用是否Random.Next()总是产生相同的数字.
最小的工作示例如下.
using System;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
const int seed = 12345;
Random rnd = new Random(seed);
for (int x = 0; x < 10; x++)
Console.WriteLine(rnd.Next());
}
}
}
Run Code Online (Sandbox Code Playgroud) 我有一个文本框和一个按钮.该按钮调用Ping(),我希望显示ping的任何进度textBox1.
void Ping()
{
p = new Process();
p.StartInfo.FileName = "ping";
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.Arguments = "www.microsoft.com";
p.Start();
textBox1.Text = p.StandardOutput.ReadToEnd();
p.WaitForExit();
}
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怎么实现呢?我上面写的当前实现并未显示进度,而是显示最终输出.
static void Main(string[] args)
{
int[][] data =// new int[][] has been omitted here!
{
new int[] {1,2,3},// new int[] cannot be omitted
new int[] {1,2,3,4}// new int[] cannot be omitted
};
Foo(new[] { 1, 2, 3 });// new[] cannot be omitted
}
static void Foo(int[] data) {/* implementation omitted */}
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为什么不能new int[]和new[]对参数和数组元素可以省略?
我不想调用
var element = document.getElementById('ph');
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每次UpdateClock为了效率而被召唤.所以我试图把它放在全球而不是放在里面UpdateClock.但是,它不起作用.
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>This is a title</title>
<script>
var element = document.getElementById('ph');
function UpdateClock() {
var now = new Date();
var hours = now.getHours();
var minutes = now.getMinutes();
var seconds = now.getSeconds();
if (hours < 10)
hours = "0" + hours;
if (minutes < 10)
minutes = "0" + minutes;
if (seconds < 10)
seconds = "0" + seconds;
element.innerHTML = hours + ":" + minutes + ":" …Run Code Online (Sandbox Code Playgroud) using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Web;
using System.Web.Mvc;
namespace MvcMusicStore.Controllers
{
public class StoreController : Controller
{
//
// GET: /Store/
public string Index()
{
// ERROR call extension method here
return GetMemberName();
}
}
public static class Utilities
{
public static string GetMemberName(this Controller caller, [CallerMemberName] string memberName = "")
{
return caller.GetType().FullName + "." + memberName;
}
}
}
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我的扩展方法无法识别,有什么问题?
我不知道以下内部实现.简而言之,哪一个在性能上更有效,x>=a或者x>a || x==a?
我们将其分为两种情况:
当两个a和x是在同一类型.
何时a和x不属于同一类型.
为什么我需要在以下字符串中加倍{但只有一个}?
static void Main()
{
Console.Write("a={0}, b={1}, c={{", 1, 2);
foreach (var i in Enumerable.Range(1, 5)) Console.Write("{0},",i);
Console.WriteLine("\b}");
}
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如何使用Linq查询方法将字符串数组转换为句子?
private static void Main()
{
string sentence = "C# is fun.";
string[] words = sentence.Split();
//string temp= words;
}
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在temp希望有相同的值sentence.
<p>
Your name: @Html.TextBoxFor
(x => x.Name)
</p>
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<p>
Your name: @Html.TextBoxFor(
x => x.Name)
</p>
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为什么我们不能将方法名称与左括号分开,(以便每个都有自己的行?
是否有一个技巧可以绕过这个功能(或可能是一个错误)?