DataGridView title bar Color setting is invalid ...

Setting the Datagridview.columnheaderdefaultcellstyle BackColor property will find no effect. This is because the values of BackColor and ForeColor are ignored when visual styles are started. To solve is very simple: dataGridView1. Enableheadersvisualstyles = false; Gets or sets a value that indicates whether the row and column headings use the visual style of the user's current theme when visual styles are enabled for the application.

//datagridview.autoresizecolumnheadersheight ();
           //datagridview.autoresizerowheaderswidth (datagridviewrowheaderswidthsizemode.autosizetodisplayedheaders);
           //datagridview.rowheaderswidthsizemode = Datagridviewrowheaderswidthsizemode.autosizetoallheaders;
           //datagridview.selectionmode = Datagridviewselectionmode.fullrowselect;
           //datagridview.readonly = true;
           //datagridview.allowusertoaddrows = false;
           //datagridview.backgroundcolor = Color.White;

Property
Datagridview.enableheadersvisualstyles = false;

Datagridview.allowusertoaddrows = false;//Prevents users from adding rows

Datagridview.allowusertoresizecolumns = false;//Prevents users from resizing columns

Datagridview.allowusertoresizerows = false;//Prevents users from resizing rows

Datagridview.selectionmode = system.windows.forms.datagridviewselectionmode.fullrowselect;//How to select a cell

Datagridview.rowheadersvisible = false; Whether to show the wardrobe

Datagridview.columnheadersvisible = false; Whether to display column headers

Datagridview.autogeneratecolumns = false; Whether to create columns automatically

Datagridview.multiselect = false; Can I select multiple rows
Style

Datagridview.columnheadersborderstyle = system.windows.forms.datagridviewheaderborderstyle.sunken;//column header border style
Datagridview.rowheadersborderstyle = system.windows.forms.datagridviewheaderborderstyle.sunken;//Wardrobe Border Style

DataGridViewCellStyle dataGridViewCellStyle1 = Datagridview.alternatingrowsdefaultcellstyle; Odd-numbered row cell style
DataGridViewCellStyle dataGridViewCellStyle3 = Datagridview.rowsdefaultcellstyle; Row cell Default Style
DataGridViewCellStyle dataGridViewCellStyle3 = Datagridview.rowheadersdefaultcellstyle; Wardrobe cell style
DataGridViewCellStyle dataGridViewCellStyle2 = Datagridview.columnheadersdefaultcellstyle; Column header cell style

Odd-numbered row cell style settings
Datagridviewcellstyle1.backcolor = System.Drawing.Color.LightYellow;

Wardrobe Cell style settings
datagridviewcellstyle3.alignment = system.windows.forms.datagridviewcontentalignment.middleleft;//Content Location
Datagridviewcellstyle3.backcolor = system.drawing.color.darkred;//Background
Datagridviewcellstyle3.font = new System.Drawing.Font ("XXFarEastFont-Arial", 9F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte) (134));//font
Datagridviewcellstyle3.forecolor = system.drawing.color.white;//Font Color
Datagridviewcellstyle3.selectionbackcolor = system.drawing.systemcolors.highlight;//Background When selected
Datagridviewcellstyle3.selectionforecolor = system.drawing.systemcolors.highlighttext;//Font Color When selected
Datagridviewcellstyle3.wrapmode = display format when cell contents are too long system.windows.forms.datagridviewtristate.true;//

Column header cell style settings
Datagridviewcellstyle2.alignment = System.Windows.Forms.DataGridViewContentAlignment.MiddleCenter;
Datagridviewcellstyle2.backcolor = System.Drawing.Color.DarkRed;
Datagridviewcellstyle2.font = new System.Drawing.Font ("XXFarEastFont-Arial", 9F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte) (134));
Datagridviewcellstyle2.forecolor = System.Drawing.Color.White;
Datagridviewcellstyle2.selectionbackcolor = System.Drawing.SystemColors.Highlight;
Datagridviewcellstyle2.selectionforecolor = System.Drawing.SystemColors.HighlightText;
Datagridviewcellstyle2.wrapmode = System.Windows.Forms.DataGridViewTriState.True;

for (int i = 0; i < Datagridview.columncount; i++)
{
Datagridview.columns[i]. Width = (datagridview.width/*-datagridview.rowheaderswidth*/)/datagridview.columncount;
}