在C＃中的For循环中发现问题 [英] Problem Found in For Loop in C#

问题描述

Hello All

实际上我没有遇到问题。我试图从数据库传递值作为上一个值（PreValue）和从文本框字段（CurValue）和FieldValue执行的当前值从数据库列名称。我将比较如果PreValue不等于CurValue，那么记录将保存到表中。我也没有获得PreValue数组格式。我对这段代码很困惑。实际上我想检查值，如果任何更改CurVale与PreVale然后循环将工作否则。任何人帮助我我的不匹配。



<前lang =c＃> 字符串 [] PreValue = < span class =code-keyword> new string [] {Program.GetCharacterValue（ 从SCVBAE中选择FaName，MoName，Address，HasAE，Misuse，其中FormSL =' + txtFrmSerial.Text.Trim（）+ 'AND PID =' + txtPID.Text.Trim（）+ '）};

string [] FieldValue = new string [ 54 ] { FaName， MoName， 地址， HasAE， 滥用};

string [] CurValue = new string [ 54 ] {txtFaName.Text，txtMoName.Text，txtAddress.Text，txtHasAE.Text，txtMisuse.Text};

尝试
{
AEProperty Add = new AEProperty（）;
Add.FormSl = txtFrmSerial.Text.Trim（）;
Add.PID = txtPID.Text;

for （ int i = 0 ; i < 6 ; i ++）
{
if （PreValue [i] .ToString（）！= CurValue [i] .ToString（））
{
Add.PreValue = PreValue [I]的ToString（）;
Add.CurValue = CurValue [i] .ToString（）;
Add.FieldName = FieldValue [i] .ToString（）;
Add.FileNo = 1;
Add.ReasonADT = 打孔错误;
Add.UpdateBy = Program.EnterBy;
Add.UpdateDt = DateTime.Today.ToString（ MM / dd / yyyy） ;
Add.UpdateTm = DateTime.Now.ToString（ HH：mm：ss tt ）;

DSDBHandler AddHandler = new DSDBHandler（）;
AddHandler.AddADT（Add）;
}
}
}
catch （例外情况）
{
MessageBox.Show （ 记录无法插入！正确检查 + ex.Message）;
txtFrmSerial.Focus（）;
}

解决方案

在循环中，看看这一行：

 Add.FieldName = FieldValue [i] .ToString（）; 

FieldValue [i] 可以有一个最大值 i 5 ，因为那是仍然符合循环条件的最大整数 i< 6 。



但是 FieldValue [5] 不存在。 FieldValue 有5名成员。数组在C＃中是零基础，因此范围从 0 到 4 。



如何解决我不知道，因为我不知道该代码应该做什么。数组 FieldValue 和 CurValue 都被54个项目声明，但只有5个被定义。 br $> b $ b





我刚用VS2008查看过。 FieldValue 和 CurValue 的声明甚至无法编译。



删除两次出现的54。然后，使用其中一个作为循环边界：

  string  [] FieldValue =  new   string  [] {  FaName，  MoName， < span class =code-string> Address，  HasAE， 误用}; 
 
  string  [] CurValue =  new   string  [] {txtFaName.Text，txtMoName.Text，txtAddress.Text，txtHasAE.Text，txtMisuse.Text}; 
 
  //   [..]  
 
  for （ int  i =  0 ; i <  FieldValue.Length; i ++）
 {

[/ Edit]

索引将从0到53，因为每个数组中有54个项目。

更改循环：

 for（int i = 0; i< 55; i ++）

to

 for（int i = 0; i< 54; i ++）

否则它将捕获超出约束的异常。

Hello All
Actually I am not getting problem. I am trying to pass value from database as Previous Value(PreValue) and Current value carrying out from text box field(CurValue) and FieldValue is taking from database column name. I will just compare if PreValue not equal to CurValue then the record will be saved into table. I am not getting PreValue array format also. I am confused about that code. Actually I want to check value if any changes CurVale with PreVale then Loop will work else not. Anybody help me my mismatch.

string[] PreValue = new string[] { Program.GetCharacterValue("Select FaName,MoName,Address,HasAE,Misuse from SCVBAE where FormSL='" + txtFrmSerial.Text.Trim() + "' AND PID='" + txtPID.Text.Trim() + "'") };

string[] FieldValue = new string[54] { "FaName","MoName","Address","HasAE","Misuse" };

string[] CurValue = new string[54] { txtFaName.Text, txtMoName.Text, txtAddress.Text, txtHasAE.Text, txtMisuse.Text };

            try
            {
                AEProperty Add = new AEProperty();
                Add.FormSl = txtFrmSerial.Text.Trim();
                Add.PID = txtPID.Text;

                for (int i = 0; i < 6; i++)
                {
                    if (PreValue[i].ToString() != CurValue[i].ToString())
                    {
                        Add.PreValue = PreValue[i].ToString();
                        Add.CurValue = CurValue[i].ToString();
                        Add.FieldName = FieldValue[i].ToString();
                        Add.FileNo = "1";
                        Add.ReasonADT = "Punching error";
                        Add.UpdateBy = Program.EnterBy;
                        Add.UpdateDt = DateTime.Today.ToString("MM/dd/yyyy");
                        Add.UpdateTm = DateTime.Now.ToString("HH:mm:ss tt");

                        DSDBHandler AddHandler = new DSDBHandler();
                        AddHandler.AddADT(Add);
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("Record cannot insert ! check properly" + ex.Message);
                txtFrmSerial.Focus();
            }

解决方案

Within the loop, look at this line:

Add.FieldName = FieldValue[i].ToString();

FieldValue[i] can have a maximum i of 5, since that's the largest integer that still conforms the loop condition i < 6.

But FieldValue[5] doesn't exist. FieldValue has 5 members. Arrays are "zero-based" in C# and therefore range from 0 to 4.

How to solve that I have no idea, since I don't know what that code should do. I'm baffled by the arrays FieldValue and CurValue being both declared with 54 items, but having only 5 defined.


[Edit]
I just checked with VS2008. The declarations of FieldValue and CurValue don't even compile.

Drop both occurances of "54". Then, use one of them as loop boundary:

string[] FieldValue = new string[] { "FaName","MoName","Address","HasAE","Misuse" };
 
string[] CurValue = new string[] { txtFaName.Text, txtMoName.Text, txtAddress.Text, txtHasAE.Text, txtMisuse.Text };

// [..]

    for (int i = 0; i < FieldValue.Length; i++)
    {

[/Edit]

Index will go from 0 to 53 as you are having 54 items in each array.
change your loop from :

for (int i = 0; i < 55; i++)

to

for (int i = 0; i < 54; i++)

else it will catch out of bound exception.

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