object a = "1";
object b = "1";
Console.WriteLine(a == b); // returns True
object c = 1;
object d = 1;
Console.WriteLine(c == d); // returns False
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上面的代码返回整数和字符串的不同结果.我无法理解为什么.有人可以帮我理解这背后的原因吗?
==(运营商)和ReferenceEquals(功能)有什么区别?
我有以下JavaScript代码.
var emoticons = {
':)': '<span class="emoticon emoticon_smile"></span>',
':-)': '<span class="emoticon emoticon_smile"></span>',
':(': '<span class="emoticon emoticon_sad"></span>',
':d': '<span class="emoticon emoticon_bigSmile"></span>',
':D': '<span class="emoticon emoticon_bigSmile"></span>'
}
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现在要用给定文本中的span替换情感我正在使用以下函数
function Emotions (text) {
if (text == null || text == undefined || text == "") return;
var pattern = /[:\-)(D/pPy@'*]+/gi;
return text.replace(pattern, function (match) {
return typeof emoticons[match] != 'undefined' ?
emoticons[match] :
match;
});
}
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现在上面的代码工作正常.如果我在函数中传递文本如下
Emotions("Hey this is a test :( :(");
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看到两种情绪之间的空间.但如果我删除两种情感之间的空间,那么它就不起作用.如下所示
Emotions("Hey this is a test :(:(");
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我的正则表达式有问题,但我无法弄明白.
我有这段代码来显示用户可以选择的颜色列表:
<form>
<h4>mat-select</h4>
<mat-form-field appearance="fill">
<mat-label>Favorite Color</mat-label>
<mat-select [(ngModel)]="selectedValue" name="food">
<mat-option *ngFor="let color of allColors" [value]="'#' + color.value">
<!-- {{color.label}} -->
<span class="color-span" [ngStyle]="{ 'background-color': '#' + color.value }"></span>
</mat-option>
</mat-select>
</mat-form-field>
</form>
import {Component} from '@angular/core';
/**
* @title Select in a form
*/
@Component({
selector: 'select-form-example',
templateUrl: 'select-form-example.html',
})
export class SelectFormExample {
public allColors: any[] = [
{label: 'FFFFFF', value: 'FFFFFF'},
{label: '000000', value: '000000'},
{label: '603813', value: '603813'},
{label: 'FF0000', value: 'FF0000'},
{label: '2E3192', value: '2E3192'}, …Run Code Online (Sandbox Code Playgroud)