从文本文件中读取错误

Question

这是我的代码，它从文本文件中读取并将其放置在窗体上的列表框中。如果文本文件中已经有东西可以使用。但是，如果我删除了文本文件中的内容并运行程序，它会崩溃并给我提供错误“索引超出了数组范围”。

在assignment.Request.Name = columns[1];我不知道为什么/如何去解决它。

public static List<Assignment> GetAssignment() 
    { 
     if (!Directory.Exists(dir)) 
      Directory.CreateDirectory(dir); 


     StreamReader textIn = 
      new StreamReader(
       new FileStream(path3, FileMode.OpenOrCreate, FileAccess.Read)); 

     List<Assignment> assignments = new List<Assignment>(); 

     while (textIn.Peek() != -1) 
     { 
      string row = textIn.ReadLine(); 
      string[] columns = row.Split('|'); 
      Assignment assignment = new Assignment(); 

      assignment.Employee.Name = columns[0]; 
      assignment.Request.Name = columns[1]; 
      assignments.Add(assignment); 
     } 

     textIn.Close(); 

     return assignments; 
    } 

Answer 1

你需要确保有柱阵列中至少2项，否则它会尝试访问数组项不存在：

while (textIn.Peek() != -1) 
     { 
      string row = textIn.ReadLine(); 
      string[] columns = row.Split('|'); 
      if(columns.length>=2) 
      { 
      Assignment assignment = new Assignment(); 

      assignment.Employee.Name = columns[0]; 
      assignment.Request.Name = columns[1]; 
      assignments.Add(assignment); 
      } 
     } 

Answer 2

把条件读完文件后。

if(columns.length >2) 
{ 

assignment.Employee.Name = columns[0]; 
      assignment.Request.Name = columns[1]; 
      assignments.Add(assignment); 

}