将"高"精度Double转换为Decimal时,由于Rounding,我将使用Convert.ToDecimal或转换为(Decimal)而失去精度.
示例:
double d = -0.99999999999999956d;
decimal result = Convert.ToDecimal(d); // Result = -1
decimal result = (Decimal)(d); // Result = -1
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Convert.ToDecimal(double)返回的Decimal值最多包含15位有效数字.如果value参数包含超过15个有效数字,则使用舍入舍入为最接近的数字.
所以为了保持我的精度,我必须将我的double转换为String然后调用Convert.ToDecimal(String):
decimal result = System.Convert.ToDecimal(d.ToString("G20")); // Result = -0.99999999999999956d
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这个方法是有效的,但是我想避免使用String变量来将Double转换为Decimal而不用15位后的舍入?
是否可以以角度2动态设置路由器插座的名称?我需要创建一个包含路由器插座的通用组件.
模板示例:
<nav class="nav menu">
<a *ngFor="let navRoute of navigationRoutes" class="nav-link" [class.selected]="navRoute.isActive" (click)="onActivated(navRoute.route)">{{navRoute.header}}</a>
</nav>
<router-outlet name=[[DO SOME BINDING HERE]]></router-outlet>
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navigationRoutes和name是组件@inputs
是否存在将String转换为Double比Convert.ToDouble 更快的方法?
我监视过System.Convert.ToDouble(String)调用并降低了我的应用程序性能.
Convert.ToDouble("1.34515");
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Jeffrey Sax的工作答案:
static decimal[] decimalPowersOf10 = { 1m, 10m, 100m, 1000m, 10000m, 100000m, 1000000m };
static decimal CustomParseDecimal(string input) {
long n = 0;
int decimalPosition = input.Length;
for (int k = 0; k < input.Length; k++) {
char c = input[k];
if (c == '.')
decimalPosition = k + 1;
else
n = (n * 10) + (int)(c - '0');
}
return n / decimalPowersOf10[input.Length - decimalPosition];
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}

我有两个绑定到属性(Side)的DataTriggers,但只能启动一个故事板(最后一个DataTriggers中的一个).
为什么?
我觉得最后一个故事板覆盖了第一个故事板
<Border x:Name="layout" Background="Transparent" BorderBrush="#BAC8CE" BorderThickness="1" CornerRadius="5">
<Border.Style>
<Style TargetType="{x:Type Border}">
<Style.Triggers>
<DataTrigger Binding="{Binding Side}" Value="Up">
<DataTrigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<ColorAnimation Storyboard.TargetProperty="(Background).(SolidColorBrush.Color)"
Duration="00:00:01"
From="Transparent"
To="Green"/>
<ColorAnimation Storyboard.TargetProperty="(Background).(SolidColorBrush.Color)"
Duration="00:00:00.5"
From="Green"
To="Transparent"/>
</Storyboard>
</BeginStoryboard>
</DataTrigger.EnterActions>
</DataTrigger>
<DataTrigger Binding="{Binding Side}" Value="Down">
<DataTrigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<ColorAnimation Storyboard.TargetProperty="(Background).(SolidColorBrush.Color)"
Duration="00:00:01"
From="Transparent"
To="Red"/>
<ColorAnimation Storyboard.TargetProperty="(Background).(SolidColorBrush.Color)"
Duration="00:00:00.5"
From="Red"
To="Transparent"/>
</Storyboard>
</BeginStoryboard>
</DataTrigger.EnterActions>
</DataTrigger>
</Style.Triggers>
</Style>
</Border.Style>
</Border>
Run Code Online (Sandbox Code Playgroud) 如何将Remoting.ObjectHandle转换为UserControl类型?
我想动态实现UserControl:
UserControl myUserControl = (UserControl)Activator.CreateInstance(Assembly.GetExecutingAssembly().FullName, "Client.IndexView");
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错误:无法将'System.Runtime.Remoting.ObjectHandle'类型的表达式转换为'UserControl'
如何使用ASP.NET 5禁用客户端验证?
我试着在config.json中将ClientValidationEnabled设置为false,就像这里一样,但我仍然data-val-*在html元素中有属性.
答案:
services.AddMvc()
.ConfigureMvcViews(options =>
{
options.HtmlHelperOptions.ClientValidationEnabled = false;
});
Run Code Online (Sandbox Code Playgroud) 如何使用EF7 RC2抑制环境事务警告?
所述SuppressAmbientTransactionWarning()方法不能被发现.
c# ×4
silverlight ×2
wpf ×2
activator ×1
angular ×1
asp.net-core ×1
datatrigger ×1
decimal ×1
double ×1
performance ×1
precision ×1
reflection ×1
storyboard ×1
typescript ×1
validation ×1