SerAndDeser.pas(298):W1036变量'tForm'可能尚未初始化

Question

有一个代码

for j := 0 to mForm.ComponentCount - 1 do
    if mForm.Components[j] is TableFormInfo then
      //try
        //table := nil;
        //tempFmtable := nil;
        //tForm := nil;

        tForm := mForm.Components[j] as TableFormInfo;

        table := TTableSpec(DBSchema.Tables.FindComponent(tForm.Table));
        tempFmtable := TfmTableData.Create(MainWindow);
        tempFmtable.Name := tForm.Name;
        tempFmtable.tname := tForm.Table;
        //tempFmtable.Caption := Utf8ToAnsi(table.Description);
        tempFmtable.Left := tForm.LeftValue;
        tempFmtable.Top := tForm.TopValue;
        tempFmtable.Height := tForm.HeightValue;
        tempFmtable.Width := tForm.WidthValue;

        tempFmTable.IBQuery1.SQL.Clear;
        tempFmtable.IBQuery1.SQL.Add('select * from ' + table.Name);
        tempFmtable.IBQuery1.Open;
        tempFmtable.DragKind:=dkDock;
        tempFmtable.DragMode:=dmAutomatic;

        i := 0;
        querystr:='select ';
        while i <= tForm.ComponentCount - 1 do
          begin
          if tForm.Components[i] is TableFieldInfo then
          begin
            //querystr:='select ';
            //field := nil;
            //tempFmtable.Show;
            field := tForm.Components[i] as TableFieldInfo;
            tempFmtable.Caption:=tForm.Caption;
            tempFmtable.DBGrid1.Columns[i].FieldName := field.FieldNameValue;
            tempFmtable.DBGrid1.Columns[i].Title.Caption := field.DescriptionValue;
            tempFmtable.DBGrid1.Columns[i].Index := field.IndexValue;
            tempFmtable.DBGrid1.Columns[i].Visible := field.VisibleValue;
            tempFmtable.DBGrid1.Columns[i].Width:=field.WidthValue;
            //tempFmtable.CheckListBox1.Items.Add(field.Description);
            //tempFmtable.CheckListBox1.Checked[i] := field.Visible;
            //tempFmtable.Show;
             if field.VisibleValue  then querystr:=querystr+ConvertNameField(field.FieldNameValue)+', ';
          end;
            //inc(i);
          if tForm.Components[i] is SettingsFormInfo then
            begin
              //sForm:=nil;
              sForm:=tForm.Components[i] as SettingsFormInfo;
              tempsettings := TfmSettings.Create(tempFmtable);
              tempsettings.Caption:=sForm.Caption;
              //tempsettings := TfmSettings.Create(tempFmtable);
              tempsettings.Name := sForm.Name;
              tempsettings.Left := sForm.LeftValue;
              tempsettings.Top := sForm.TopValue;
              tempsettings.Height := sForm.HeightValue;
              tempsettings.Width := sForm.WidthValue;
              tempSettings.CheckListBox1.Clear;
              //for k:=0 to sForm.ComponentCount-1 do
              k:=0;
              while k<=sForm.ComponentCount-1 do
                begin
                  if sForm.Components[k] is ItemCheckListBoxInfo then
                    begin
                      //item:=nil;
                      item:=sForm.Components[k] as ItemCheckListBoxInfo;
                      tempsettings.CheckListBox1.Items.Add(item.TextValue);
                      tempsettings.CheckListBox1.Checked[item.IndexValue]:=item.CheckedValue
                    end;
                  if sForm.Components[k] is LabelInfo then
                    begin
                      //labelobj:=nil;
                      labelobj:=sForm.Components[k] as LabelInfo;
                      tempsettings.Label1.Caption:=labelobj.CaptionValue;
                    end;
                  if sForm.Components[k] is EditInfo then
                    begin
                      //edit:=nil;
                      edit:=sForm.Components[k] as EditInfo;
                      TEdit(tempsettings.FindComponent(edit.Name)).Text:=edit.TextValue;
                    end;
                    inc(k);
                end;
             if ((tForm.Components[i] is SettingsFormInfo) and (i=tForm.ComponentCount-1) and (k=sForm.ComponentCount)) then tempsettings.Show;
            end;
             //inc(i);
             //if ((tForm.Components[i] is SettingsFormInfo) and (i=tForm.ComponentCount-1) and (k=sForm.ComponentCount)) then tempsettings.Show;
             inc(i);
          end;

        {for i := 0 to table.Fields.ComponentCount - 1 do
        begin
          descr := Utf8ToAnsi(((table.Fields.Components[i]) as TFieldSpec).Description);
          tempFmtable.CheckListBox1.Items.Add(descr);
          tempFmtable.DBGrid1.Columns[i].Title.Caption := descr;
          tempFmtable.CheckListBox1.Checked[i] := true;
        end; }

        Delete(querystr, Length(querystr)-1, 1);
        querystr:=querystr+'from '+table.Name;
        tempFmTable.IBQuery1.SQL.Clear;
        tempFmtable.IBQuery1.SQL.Add(querystr);
        tempFmtable.IBQuery1.Open;
        for s := 0 to tForm.ComponentCount-1 do
          begin
            if tForm.Components[s] is TableFieldInfo then
              begin
                //field := nil;
                //tempFmtable.Show;
                field := tForm.Components[s] as TableFieldInfo;
                if field.VisibleValue then
                   begin
                     for t := 0 to tempFmtable.DBGrid1.Columns.Count-1 do
                       begin
                       if ((tempFmTable.DBGrid1.Columns[t].Title.Caption=field.DescriptionValue) and (tempFmtable.DBGrid1.Columns[t].FieldName=field.FieldNameValue)) then
                           tempFmTable.DBGrid1.Columns[t].Width:=field.WidthValue;
                       end;
                   end;
              end;
          end;
        tempFmtable.Show;

通过反序列化进入条件.我想在tForm变量使用之前标记它

table := TTableSpec(DBSchema.Tables.FindComponent(tForm.Table));

它在前一行中初始化

tForm := mForm.Components[j] as TableFormInfo;

但尽管在组装期间发生了这种警告

[dcc32 Warning] SerAndDeser.pas(298): W1036 Variable 'tForm' might not have been initialized

为什么？如何在不丢失应用程序功能的情况下摆脱警告？

Answer 1

你的缩进都很糟糕.我认为这让你感到困惑.如果您正确缩进代码,它看起来像这样:

for j := 0 to mForm.ComponentCount - 1 do
  if mForm.Components[j] is TableFormInfo then
    // try
    // table := nil;
    // tempFmtable := nil;
    // tForm := nil;

    tForm := mForm.Components[j] as TableFormInfo;

table := TTableSpec(DBSchema.Tables.FindComponent(tForm.table));

我认为现在可以清楚地看到for循环之后的代码可以在没有tForm分配的情况下执行.

从问题中的缩进中可以清楚地看出,您希望在赋值之后的大量代码位于if语句中.但编译器遵循代码而不是缩进.

您将需要begin/end在代码中添加一些对.我个人从不使用单一语句语法 - 我的所有块都是用begin/end对包裹的复合块.在我看来,单个语句语法是Pascal的一个重大错误.确实是C.

我使用内置的代码格式化程序来理顺你的缩进.这可能是一个有用的工具,可以帮助您修复代码.它可以让你掌握如何正确布局缩进.

最后,正如我之前至少对你说的那样,不要tForm用作变量名.这隐藏了名为的类型TForm.该T前缀保留类型.你应该打电话给你的表单变量Form,或许LForm与L这表明它是一个局部变量.