我有一个标签，显示的内容超过一行，我希望将文本两端对齐（左右对齐）。如何最好地实现它？
3个回答
11
另一种实现。
这个实现仅在单词之间插入“Hair Spaces”。
编辑：
添加了一个实现段落块对齐的方法。
JustifyParagraph()和JustifyLine()都调用工作方法Justify()。
label1.Text = JustifyParagraph(label1.Text, label1.Font, label1.ClientSize.Width);
public string JustifyParagraph(string text, Font font, int ControlWidth)
{
string result = string.Empty;
List<string> ParagraphsList = new List<string>();
ParagraphsList.AddRange(text.Split(new[] { "\r\n" }, StringSplitOptions.None).ToList());
foreach (string Paragraph in ParagraphsList) {
string line = string.Empty;
int ParagraphWidth = TextRenderer.MeasureText(Paragraph, font).Width;
if (ParagraphWidth > ControlWidth) {
//Get all paragraph words, add a normal space and calculate when their sum exceeds the constraints
string[] Words = Paragraph.Split(' ');
line = Words[0] + (char)32;
for (int x = 1; x < Words.Length; x++) {
string tmpLine = line + (Words[x] + (char)32);
if (TextRenderer.MeasureText(tmpLine, font).Width > ControlWidth)
{
//Max lenght reached. Justify the line and step back
result += Justify(line.TrimEnd(), font, ControlWidth) + "\r\n";
line = string.Empty;
--x;
} else {
//Some capacity still left
line += (Words[x] + (char)32);
}
}
//Adds the remainder if any
if (line.Length > 0)
result += line + "\r\n";
}
else {
result += Paragraph + "\r\n";
}
}
return result.TrimEnd(new[]{ '\r', '\n' });
}
JustifyLines() 只处理单行文本:（小于客户区域）
textBox1.Text = JustifyLines(textBox1.Text, textBox1.Font, textBox1.ClientSize.Width);
public string JustifyLines(string text, Font font, int ControlWidth)
{
string result = string.Empty;
List<string> Paragraphs = new List<string>();
Paragraphs.AddRange(text.Split(new[] { "\r\n" }, StringSplitOptions.None).ToList());
//Justify each paragraph and re-insert a linefeed
foreach (string Paragraph in Paragraphs) {
result += Justify(Paragraph, font, ControlWidth) + "\r\n";
}
return result.TrimEnd(new[] {'\r', '\n'});
}
工作方法：
private string Justify(string text, Font font, int width)
{
char SpaceChar = (char)0x200A;
List<string> WordsList = text.Split((char)32).ToList();
if (WordsList.Capacity < 2)
return text;
int NumberOfWords = WordsList.Capacity - 1;
int WordsWidth = TextRenderer.MeasureText(text.Replace(" ", ""), font).Width;
int SpaceCharWidth = TextRenderer.MeasureText(WordsList[0] + SpaceChar, font).Width
- TextRenderer.MeasureText(WordsList[0], font).Width;
//Calculate the average spacing between each word minus the last one
int AverageSpace = ((width - WordsWidth) / NumberOfWords) / SpaceCharWidth;
float AdjustSpace = (width - (WordsWidth + (AverageSpace * NumberOfWords * SpaceCharWidth)));
//Add spaces to all words
return ((Func<string>)(() => {
string Spaces = "";
string AdjustedWords = "";
for (int h = 0; h < AverageSpace; h++)
Spaces += SpaceChar;
foreach (string Word in WordsList) {
AdjustedWords += Word + Spaces;
//Adjust the spacing if there's a reminder
if (AdjustSpace > 0) {
AdjustedWords += SpaceChar;
AdjustSpace -= SpaceCharWidth;
}
}
return AdjustedWords.TrimEnd();
}))();
}
关于 RichTextBox。
@TaW 表示它不支持块对齐，但这并不完全正确。
RichTextBox 基于 RichEdit 类，该类支持“对齐”功能。
这在旧的平台 SDK 中有所报道（附有示例）。
RichTextBox 在处理创建期间明确截断了其 AdvancedTypographicsOption。
（这与实现 PARAFORMAT vs. PARAFORMAT2 结构体无关，这是故意的，与此无关）。
因此，这是解决 RichTextBox 的“良药”。
从中派生一个类，并使用 SendMessage 向基类发送 EM_SETTYPOGRAPHYOPTIONS 消息，指定 TO_ADVANCEDTYPOGRAPHY 以重新启用 Justification。
它还遮盖了 SelectionAlignment，以添加缺失的 Justify 选项。
这适用于段落级别或从某一点开始。
public class JustifiedRichTextBox : RichTextBox
{
[DllImport("user32", CharSet = CharSet.Auto)]
private static extern int SendMessage(IntPtr hWnd, int msg, int wParam, [In] [Out] ref PARAFORMAT2 pf);
[DllImport("user32", CharSet = CharSet.Auto)]
private static extern int SendMessage(IntPtr hWnd, int msg, int wParam, int lParam);
public enum TextAlignment
{
Left = 1,
Right,
Center,
Justify
}
private const int EM_SETEVENTMASK = 1073;
private const int EM_GETPARAFORMAT = 1085;
private const int EM_SETPARAFORMAT = 1095;
private const int EM_SETTYPOGRAPHYOPTIONS = 1226;
private const int TO_ADVANCEDTYPOGRAPHY = 0x1;
private const int WM_SETREDRAW = 11;
private const int PFM_ALIGNMENT = 8;
private const int SCF_SELECTION = 1;
[StructLayout(LayoutKind.Sequential)]
private struct PARAFORMAT2
{
//----------------------------------------
public int cbSize; // PARAFORMAT
public uint dwMask;
public short wNumbering;
public short wReserved;
public int dxStartIndent;
public int dxRightIndent;
public int dxOffset;
public short wAlignment;
public short cTabCount;
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 32)]
public int[] rgxTabs;
//----------------------------------------
public int dySpaceBefore; // PARAFORMAT2
public int dySpaceAfter;
public int dyLineSpacing;
public short sStyle;
public byte bLineSpacingRule;
public byte bOutlineLevel;
public short wShadingWeight;
public short wShadingStyle;
public short wNumberingStart;
public short wNumberingStyle;
public short wNumberingTab;
public short wBorderSpace;
public short wBorderWidth;
public short wBorders;
}
private int updating = 0;
private int oldEventMask = 0;
public new TextAlignment SelectionAlignment
{
// SelectionAlignment is not overridable
get
{
PARAFORMAT2 pf = new PARAFORMAT2();
pf.cbSize = Marshal.SizeOf(pf);
SendMessage(this.Handle, EM_GETPARAFORMAT, SCF_SELECTION, ref pf);
if ((pf.dwMask & PFM_ALIGNMENT) == 0) return TextAlignment.Left;
return (TextAlignment)pf.wAlignment;
}
set
{
PARAFORMAT2 pf = new PARAFORMAT2();
pf.cbSize = Marshal.SizeOf(pf);
pf.dwMask = PFM_ALIGNMENT;
pf.wAlignment = (short)value;
SendMessage(this.Handle, EM_SETPARAFORMAT, SCF_SELECTION, ref pf);
}
}
//Overrides OnHandleCreated to enable RTB advances options
protected override void OnHandleCreated(EventArgs e)
{
base.OnHandleCreated(e);
// EM_SETTYPOGRAPHYOPTIONS allows to enable RTB (RichEdit) Advanced Typography
SendMessage(this.Handle, EM_SETTYPOGRAPHYOPTIONS, TO_ADVANCEDTYPOGRAPHY, TO_ADVANCEDTYPOGRAPHY);
}
} //JustifiedRichTextBox
- Jimi
3
这太棒了，但是有可能修改它以获取"<br>"而不是rn吗？我正在使用HTML标记。我尝试过了，但无法完成。我正在使用RDLC，很难解决这个令人难以置信的问题。提前感谢任何帮助，或者如果您愿意，我可以提出一个新问题。 - Leandro Bardelli
@MacGyver，我不太确定你在这里问什么。你需要用
</br>或<br>替换\r\n或\n吗？这应该在什么时候发生？当文本导出为Html时？还是在输入时？也许提出一个问题是个好主意，这样你就可以更好地描述你的要求。这可能会很有趣。 - Jimi感谢您的回复，我已经完成了，它是用于RDLC HTML标记 :) - Leandro Bardelli
10
这是TaW提出的解决方案的实现。这只是实现的基础代码-没有自动重新调整等功能。
在操作中：
public void Justify(System.Windows.Forms.Label label)
{
string text = label.Text;
string[] lines = text.Split(new[]{"\r\n"}, StringSplitOptions.None).Select(l => l.Trim()).ToArray();
List<string> result = new List<string>();
foreach (string line in lines)
{
result.Add(StretchToWidth(line, label));
}
label.Text = string.Join("\r\n", result);
}
private string StretchToWidth(string text, Label label)
{
if (text.Length < 2)
return text;
// A hair space is the smallest possible non-visible character we can insert
const char hairspace = '\u200A';
// If we measure just the width of the space we might get too much because of added paddings so we have to do it a bit differently
double basewidth = TextRenderer.MeasureText(text, label.Font).Width;
double doublewidth = TextRenderer.MeasureText(text + text, label.Font).Width;
double doublewidthplusspace = TextRenderer.MeasureText(text + hairspace + text, label.Font).Width;
double spacewidth = doublewidthplusspace - doublewidth;
//The space we have to fill up with spaces is whatever is left
double leftoverspace = label.Width - basewidth;
//Calculate the amount of spaces we need to insert
int approximateInserts = Math.Max(0, (int)Math.Floor(leftoverspace / spacewidth));
//Insert spaces
return InsertFillerChar(hairspace, text, approximateInserts);
}
private static string InsertFillerChar(char filler, string text, int inserts)
{
string result = "";
int inserted = 0;
for (int i = 0; i < text.Length; i++)
{
//Add one character of the original text
result += text[i];
//Only add spaces between characters, not at the end
if (i >= text.Length - 1) continue;
//Determine how many characters should have been inserted so far
int shouldbeinserted = (int)(inserts * (i+1) / (text.Length - 1.0));
int insertnow = shouldbeinserted - inserted;
for (int j = 0; j < insertnow; j++)
result += filler;
inserted += insertnow;
}
return result;
}
在操作中：
- Manfred Radlwimmer
3
+1 那个间距字符的度量出现了一些问题，我将发布一个涉及单词间距的解决方案。 - Jimi
嗨@Manfred Radlwimmer！Mac OS中的TextRenderer是否有类似的功能？ - Armando Marques da S Sobrinho
这很糟糕，我想要并需要在我的标签中对齐文本，也许我可以用另一种方式来获取行的长度以替换“Testrenderer.MeasureText（...）”以实现跨平台，@ManfredRadlwimmer... - Armando Marques da S Sobrinho
9
很遗憾，只支持三种最基本和简单的对齐类型：右对齐，左对齐和居中对齐。
第四种两端对齐或块对齐在任何 .NET 控件中都不被支持。即使在 RichtTextBox 中也不支持。 :-(
唯一的解决方法是在单词之间添加空格或更好的小空格字符，如细空格(U+2009)或毛发空格 (U+200A)，直到 Label 的 Height 改变。然后向后一步，尝试找到下一个插入点，即下一行，依此类推.. 直到达到文本的末尾。
有点棘手，但不是难事。
- TaW
网页内容由stack overflow 提供, 点击上面的可以查看英文原文，
原文链接
原文链接
TextAlign，那么与你想要实现的有何不同？ - PikohMeasureString并调整单词之间的空格来实现。 - Pikoh