Question

我正在创建一个从excel表导入2d对象信息数组的程序。然后它将此数组传递给ProcessObjects方法进行处理并打印/导出回excel模板。任何人都可以告诉我为什么我收到此错误消息？

“Project.exe中发生了'System.IndexOutOfRangeException'类型的未处理异常

附加信息：索引超出了数组的范围。“

private void ProcessObjects(object[,] classesArray, object[,] classesAvailabilityArray, Excel.Workbook workbook2, Excel.Sheets excelSheets)
{
    // once classes are selected, they are copied to a temporary location
    // while they're waiting to be printed
    object[,] tempArray = new object[6,3];

    // This stops the while loop once enough credit hours have been taken 
    // It must reach 123 hours for CS Degree .
    int hourCounter = 0;

    int iteration = 0;

    while (hourCounter < 123)
        {
            // this while loop copies some classes from classesArray to tempArray
            // so they can be printed into the excel template (NewStudentTemplateCS.xlsx)
            //
            int classes = 0, hours = 0; // stops while loop if limit is reached
            int w = 0, x = 0; // used to select individual elements of tempArray (0 based)
                              // w = row
                              // x = column
            int y = 1, z = 1; // used to select individual elements of classesArray (1 based)
                              // y = row
                              // z = column
            while(classes < 7 || hours < 17)
            {
                // this loop checks the status of the flag and stops at the first avaliable
                // class/row of classesArray
                while (classesArray[y,7] == (object)1)
                {
                    y++;
                }

                // copies the call EX: "MATH 2313" from classesArray to tempArray
                tempArray[w,x] = classesArray[y,z];
                x += 2;
                z += 2;
                // copies the name EX: "Calculus I" from classesArray to tempArray
                tempArray[w, x] = classesArray[y, z];
                x++;
                z++;
                // Copies the hours EX: "3" from classesArray to tempArray
                tempArray[w, x] = classesArray[y, z];

                Console.WriteLine("debug test");

                // increments classes, hours, and hourCounter for exit decision
                classes += 1;
                hours += (int)classesArray[y, z];
                hourCounter += (int)classesArray[y, z];

                // sets flag to one
                z += 3;
                classesArray[y, z] = 1;

            }// end while loop

            // print method that prints temp array and clears tempArray for next use
            PrintArray(tempArray, iteration, workbook2, excelSheets);

            // iterates iteration
            iteration++;

        } // end while loop
        // print method that prints temp array and clears tempArray for next use
        PrintArray(tempArray, iteration, workbook2, excelSheets);

        // iterates iteration
        iteration++;

    } // end while loop
} // end ProcessObjects method

我已单独注释掉以下每一行，但每行代码都返回上面列出的相同错误。

Console.WriteLine("debug test");

// increments classes, hours, and hourCounter for exit decision
classes += 1;
hours += (int)classesArray[y, z];
hourCounter += (int)classesArray[y, z];

// sets flag to one
z += 3;
classesArray[y, z] = 1;

Answer 1

在调试器中逐步执行代码：

object[,] tempArray = new object[6,3];

您正在创建一个最大索引为tempArray[5, 2]的数组。然后你开始循环。在每个循环开始时：

int w = 0, x = 0;

然后在循环体中：

tempArray[w,x] = classesArray[y,z];

您已分配到tempArray[0, 0]

x += 2;
z += 2;
tempArray[w, x] = classesArray[y, z];

您已分配到tempArray[0, 2]

x++;
z++;
// Copies the hours EX: "3" from classesArray to tempArray
tempArray[w, x] = classesArray[y, z];

您已分配到tempArray[0, 3]。但tempArray的最大索引是[0,2];你的数组索引超出范围，正是异常告诉你的。

如果您确定y和z永远不会超出classesArray的范围，您可以像这样声明tempArray：

object[,] tempArray = new object[classesArray.GetLength(0), classesArray.GetLength(1)];

但是对于所有这些硬编码的幻数，并试图同步具有不同基数的数组，这是非常危险的代码。

Answer 2

您正在使用的整数（即w，x，y，z）变得大于定义的数组大小。您应该在代码中添加断点，以便您可以看到编译期间发生的情况，并查看它们变得比数组定义所预期的更大。

循环规则通常用于阻止索引超出范围的异常。我建议稍微分解一下代码，似乎有很多东西在继续，但对于这个循环似乎太过分了。

System.IndexOutOfRangeException - 索引超出了数组的范围

2 个答案: