CamlQuery对SharePointOnline List 发起查询请求

最近的项目中遇到了一个需求，需要向SharePointList 查询Item是否存在，找到了CamlQuery这样一个方法,但是没有找到使用这个接口的频率限制说明文档，于是就有了这篇随笔。

新接触这个方向，请大家多多指教。

	#Load SharePoint CSOM Assemblies
	Add-Type -Path "F:\Microsoft.SharePoint.Client.dll"
	Add-Type -Path "F:\Microsoft.SharePoint.Client.Runtime.dll"
	Add-Type -Path "F:\Microsoft.SharePoint.Client.Publishing.dll"
	#Variables for Processing
	$SiteUrl = "<app web url>"
	$ListName="<ListTitle>"
	 
	$UserName="<account>"
	$Password ="<password>"
	  
	#Setup Credentials to connect
	$Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($UserName,(ConvertTo-SecureString $Password -AsPlainText -Force))
	  
	#Set up the context
	$Context = New-Object Microsoft.SharePoint.Client.ClientContext($SiteUrl)
	$Context.Credentials = $credentials

	$List = $Context.web.Lists.GetByTitle('<ListTitle>')

	$Title="Test"
	$start = Get-Date
	for($i=0;$i -le 1000;$i++)
	{
		try
		{     

		$Query = New-Object Microsoft.SharePoint.Client.CamlQuery;
		$Query.ViewXml = "<View><Query><Where><Eq><FieldRef Name='Title' /><Value Type='Text'>"+$Title+"</Value></Eq></Where></Query></View>"
		$ListItems = $list.GetItems($Query);
		$Context.Load($ListItems)
		$Context.ExecuteQuery()
		$midend = Get-Date
		write-host "Test"+$i+"Do"+($midend - $start).TotalSeconds

		"Test"+$i+"Do"+($midend - $start).TotalSeconds | Out-File -Append d:\PsTest.txt
		}
		catch [System.Exception]
		{
		$midend = Get-Date
		# write-host "Test"$i "Error" ($midend - $start).TotalSeconds
		"Test"+$i+"Error"+($midend - $start).TotalSeconds | Out-File -Append d:\PsTest.txt
        write-host -f red $_.Exception.ToString()
		}
	}
		$end = Get-Date
		write-host "Test"$i "Console"($end - $start).TotalSeconds
		"Test"+$i+"Console"+($end - $start).TotalSeconds| Out-File -Append d:\PsTest.txt

　　根据返回的结果统计来看，1000次顺序Query请求成功率为100%，曲线如下

1000次的Query查询大概用时238.46秒，曲线中纵轴为响应的返回时间，整体看来曲线还不错，回来进行一下并行测试的的情况。