Alignment:
Refers to the placement of text within a cell. Followings are the basic alignments which can be applied over a cell content:
- Left : puts text horizontally left in a cell
- Right : puts text horizontally right in a cell
- Center : puts text horizontally center in a cell
- Distributed : puts text vertically distributed in a cell
- Justify : puts text vertically justify in a cell
- Top : puts text vertically top in a cell
- Middle: puts text vertically center in a cell
- Bottom : puts text vertically bottom in a cell
Let’s put some example to understand each alignment, I am taking following source to understand alignment:

Based on above input, we will put code to check each output
Left Align:
private void btnLeft_Click(object sender, RibbonControlEventArgs e) { //Capture user selection excel.Range oRange = Globals.ThisAddIn.Application.Selection; //Align text oRange.HorizontalAlignment = excel.XlHAlign.xlHAlignLeft; }
Output:

Right Align:
private void btnRight_Click(object sender, RibbonControlEventArgs e) { //Capture user selection excel.Range oRange = Globals.ThisAddIn.Application.Selection; //Align text oRange.Cells.HorizontalAlignment = excel.XlHAlign.xlHAlignRight; }
Output:

Center Align:
private void btnCenter_Click(object sender, RibbonControlEventArgs e) { //Capture user selection excel.Range oRange = Globals.ThisAddIn.Application.Selection; //Align text oRange.Cells.HorizontalAlignment = excel.XlHAlign.xlHAlignCenter; }
Output:

Top Align:
private void btnTopAlign_Click(object sender, RibbonControlEventArgs e) { //Capture user selection excel.Range oRange = Globals.ThisAddIn.Application.Selection; //Align text oRange.Cells.VerticalAlignment = excel.XlVAlign.xlVAlignTop; }
Output:

Middle Align:
private void btnMiddle_Click(object sender, RibbonControlEventArgs e) { //Capture user selection excel.Range oRange = Globals.ThisAddIn.Application.Selection; //Align text oRange.Cells.VerticalAlignment = excel.XlVAlign.xlVAlignCenter; //Middle }
Output:

Bottom Align:
private void btnBottom_Click(object sender, RibbonControlEventArgs e) { //Capture user selection excel.Range oRange = Globals.ThisAddIn.Application.Selection; //Align text oRange.Cells.VerticalAlignment = excel.XlVAlign.xlVAlignBottom; }
Output:

Distributed Align:
private void btnDistributed_Click(object sender, RibbonControlEventArgs e) { //Capture user selection excel.Range oRange = Globals.ThisAddIn.Application.Selection; //Align text oRange.Cells.VerticalAlignment = excel.XlVAlign.xlVAlignDistributed; }
Output:

Justify Alignment:
private void btnJustify_Click(object sender, RibbonControlEventArgs e) { //Capture user selection excel.Range oRange = Globals.ThisAddIn.Application.Selection; //Align text oRange.Cells.VerticalAlignment = excel.XlVAlign.xlVAlignJustify; }
Output:

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