if($value-eq$null) {'The array is $null'}if($value-ne$null) {'The array is not $null'} 如果我未定义$value,则第一个的计算结果为$true,消息为The array is $null。 这里的陷阱是,可以创建一个允许二者都为$false的$value PowerShell $value= @($null)
三元运算符? <if-true> : <if-false> 在简单的条件情况下,可以使用三元运算符替代if-else语句。 有关详细信息,请参阅about_If。 Null 合并操作符?? 如果null 合并运算符??不为 null,则它返回其左操作数的值。 否则,它将计算右操作数并返回其结果。 如果左操作数的计算结果为非 null,则??运算符不会计...
代码: //判断是否是正整数 function IsNum(s) { if(s!...=null){ var r,re; re = /\d*/i; //\d表示数字,*表示匹配多个数字 r = s.match(re); return...true:false; } return false; } //判断是否为数字 function IsNum(s) { if (s!=null && s!
Checking if a string is NULL or EMPTY is very common requirement in Powershell script. If we don’t do that we will end up with run time errors if we try to perform some operation on that string variable which is empty or null. So the question now is, how to check it? Well, belo...
// Trigger on errorif(target == FeedbackTrigger.Error) {// Gets the command that caused the error.varerroredCommand = context.LastError?.InvocationInfo.MyCommand;if(erroredCommandisnull) {returnnull; } header =$"You have triggered an error with the command{erroredCommand}. Try using the fo...
This is planned ***`n`n\"\n\ Read-Host\n"; InvokeMethod(spType, L"InvokePS", argument); Cleanup: if (pCorRuntimeHost) { pCorRuntimeHost->Release(); pCorRuntimeHost = NULL; } return 0; } void InvokeMethod(_TypePtr spType, wchar_t* method, wchar_t* command) { HRESULT hr...
but it can take time and we always question if it’s worth it. I can write a PowerShell script and automate that script fairly easily, only because I have done this many times. Finding the time to automate our simple and repeatable tasks is the first blocker. Does...
[System.ComponentModel.TypeConverter(typeof(Microsoft.Azure.PowerShell.Cmdlets.EventGrid.Models.IsNullOrUndefinedFilterTypeConverter))]publicinterfaceIIsNullOrUndefinedFilter:Microsoft.Azure.PowerShell.Cmdlets.EventGrid.Models.IFilter Attributes TypeConverterAttribute ...
# Execute the SQL command with retry logic$connection= GiveMeConnectionSource$connectionStringif($connection-eq$null){Write-Host"It is not possible to connect to the database"exit;}ExecuteWithRetry 1$connection"WAITFOR DELAY '00:00:40'"$connection.Close...
{#Check the SocketErrorCode to see if it's the expected exceptionif($_.Exception.SocketErrorCode-eq[System.Net.Sockets.SocketError]::AddressAlreadyInUse) { Log"Port$PortNumberis in use."}else{ Log"SocketException on port${PortNumber}:$($_.Exception)"} } }$null}Test-PortAvailability12179...