在声明之前不能使用局部变量'Location'。 [英] Cannot use local variable 'Location' before it is declared.

问题描述

您好



我在以下代码中收到错误

在声明之前不能使用局部变量'Location'。本地变量声明隐藏字段a.form1.location。

in the br />
<预郎= CS> LOCATIONNAME =（文本框）（Location.FindControl（<跨度类= 代码串> <跨度类= 代码串>地点））;
LocationID =（TextBox）（Location.FindControl（ LocationID））;

这些行





这是我的代码

 public partial class FrmMasterAsset：System.Web.UI.Page 
 {
 
 // LQMasterAssetDataContext DB; 
 clsGeneralLib mobjGenlib; 
 public static string mSearchBy =; 
 TextBox ManufactureName; 
 TextBox ManufactureID; 
 TextBox UOMName; TextBox UOMID; 
 TextBox类别名称; TextBox CategoryID; 
 TextBox LocationName; TextBox LocationID; 
 TextBox DepartmentName; TextBox DepartmentID; 
 
 
 protected void Page_Load（object sender，EventArgs e）
 {
 // DB = new LQMasterAssetDataContext（）; 
 mobjGenlib = new clsGeneralLib（）; 
 
 //对于用户控制定义
 ManufactureName =（TextBox）（Manufacturer.FindControl（Account））; 
 ManufactureID =（TextBox）（Manufacturer.FindControl（AccountID））; 
 // UOMName =（TextBox）（UOM.FindControl（UOMType））; 
 // UOMID =（TextBox）（UOM.FindControl（UOMTypeID））; 
 CategoryID =（TextBox）（AssetCategory.FindControl（AssetCategoryID））; 
 CategoryName =（TextBox）（AssetCategory.FindControl（AssetCategory））; 
 LocationName =（TextBox）（Location.FindControl（Location））; 
 LocationID =（TextBox）（Location.FindControl（LocationID））; 
 .......... 
 ......... 
依此类推

可以提前帮助我解决这个问题。

解决方案

嗯，是的。你会的。

该代码没有声明任何名为Location的变量 - 所以你不能使用它，因为系统不知道它是什么类型，也看不到它无论如何都要获得任何价值！



可能，你正试图在当前页面找到一个控件，应该使用：

 LocationName =（TextBox）（FindControl（  Location））; 
 LocationID =（TextBox）（FindControl（  LocationID））; 

哪会检查当前页面。

您好我找到了我的上述问题的解决方案; 
 
在.aspx页面的项目中，我将注册名称 Location 更改为 AssetLocation  ...它运行正常。 
 
 
 
注意 - 在具有与其字段类似的局部变量的类的方法中，局部变量在方法中访问时隐藏字段。使用局部变量比使用字段更有效。

Hi

I'm Getting the error in the following code as

"

Cannot use local variable 'Location' before it is declared.The Declaration of Local Variable hides the field a.form1.location.

"
in the

LocationName = (TextBox)(Location.FindControl("Location"));
           LocationID = (TextBox)(Location.FindControl("LocationID"));

these lines


Here is my code

public partial class FrmMasterAsset : System.Web.UI.Page
    {

        //LQMasterAssetDataContext DB;
        clsGeneralLib mobjGenlib;
        public static string mSearchBy = "";
        TextBox ManufactureName;
        TextBox ManufactureID;
        TextBox UOMName; TextBox UOMID; 
        TextBox CategoryName; TextBox CategoryID;
        TextBox LocationName; TextBox LocationID;
        TextBox DepartmentName; TextBox DepartmentID;
        

        protected void Page_Load(object sender, EventArgs e)
        {
            //DB = new LQMasterAssetDataContext();
            mobjGenlib = new clsGeneralLib();

            //For User Control Definition
            ManufactureName = (TextBox)(Manufacturer.FindControl("Account"));
            ManufactureID = (TextBox)(Manufacturer.FindControl("AccountID"));
            //UOMName = (TextBox)(UOM.FindControl("UOMType"));
            //UOMID = (TextBox)(UOM.FindControl("UOMTypeID"));
            CategoryID = (TextBox)(AssetCategory.FindControl("AssetCategoryID"));
            CategoryName = (TextBox)(AssetCategory.FindControl("AssetCategory"));
            LocationName = (TextBox)(Location.FindControl("Location"));
            LocationID = (TextBox)(Location.FindControl("LocationID"));
..........
.........
and so on

can any one help me to resolve this thanks in advance.

解决方案

Well, yes. You will.
That code doesn't declare any variable called "Location" - so you can't use it, because the system doesn't know what type it is, and can't see it getting any value anyway!

Possibly, you are trying to find a control on the current page, and should be using:

LocationName = (TextBox)(FindControl("Location"));
LocationID = (TextBox)(FindControl("LocationID"));

Which would check the current page.

Hi i Have  found the solution for my Above issue; 

In my project in the .aspx page i changed the name Location in the Register as  AssetLocation ...it works fine. 



Note- " Within a method of a class that has a local variable named similar to its field, the local variable hides the field while accessing it within the method. It is more efficient to use a local variable than a field."

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