C# System.Array' 不包含 'Count' 的定义
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System.Array' does not contain a definition for 'Count'
提问by Siddiq Baig
In my C# Project, I am getting this error that the definition for count does not contain System.Array
在我的 C# 项目中，我收到此错误，即计数的定义不包含 System.Array
protected void Page_Prerender(object sender, EventArgs e)
{
FileInfo[] fileInfo;
string UpFolder = Server.MapPath("~/data/images/");
DirectoryInfo dir = new DirectoryInfo(UpFolder);
fileInfo = dir.GetFiles();
// here i am getting error
int TotalImages = fileInfo.Count();
for (int count = 0; count < TotalImages; count++)
{
Image image = new Image();
image.ImageUrl = "~/data/images/" + fileInfo[count].ToString();
image.ID = count.ToString();
DataListImage.Controls.Add(image);
}
DataListImage.DataSource = dir.GetFiles();
DataListImage.DataBind();
string UpFolder1 = Server.MapPath("~/data/thumbnails/");
DirectoryInfo dir1 = new DirectoryInfo(UpFolder1);
DataListthumbnails.DataSource = dir1.GetFiles();
DataListthumbnails.DataBind();
}
采纳答案by Habib
You don't need Count, instead you can use Lengthwith arrays to get the count.
您不需要Count，而是可以使用Length数组来获取计数。
You are getting the error since you are missing using System.Linq;
由于您丢失，您收到错误 using System.Linq;
To get TotalImagesyou can use
为了让TotalImages你可以使用
int TotalImages = fileInfo.Length;
回答by user2864740
While Count()isn't "needed"since the type is an Array, the error is a result of not "using" the correct namespaces.
虽然Count()不是“需要”，因为类型是一个数组，但错误是没有“使用”正确的命名空间的结果。
Enumerable.Count()is a LINQ extensionmethod in the System.Linqnamespace. As such, it can be made available with the following:
Enumerable.Count()是命名空间中的 LINQ扩展方法System.Linq。因此，它可以通过以下方式提供：
using System.Linq;
Since arrays implement IEnumerable<T>, then they can utilize any such methods when they are made available.
由于数组实现了IEnumerable<T>，因此它们可以在可用时使用任何此类方法。
