在我的RichtextBox，如果我写如下。
这是我的笔，
他的笔很漂亮。
现在我搜索单词“is”然后 输出如下。
所有“是”都应突出显示。
【问题讨论】：
RichTextBox 不适用于已接受的解决方案。
标签： c# winforms find richtextbox highlight
怎么样：
static class Utility {
public static void HighlightText(this RichTextBox myRtb, string word, Color color) {
if (word == string.Empty)
return;
int s_start = myRtb.SelectionStart, startIndex = 0, index;
while((index = myRtb.Text.IndexOf(word, startIndex)) != -1) {
myRtb.Select(index, word.Length);
myRtb.SelectionColor = color;
startIndex = index + word.Length;
}
myRtb.SelectionStart = s_start;
myRtb.SelectionLength = 0;
myRtb.SelectionColor = Color.Black;
}
}
【讨论】：
while(myRtb.Text.IndexOf(word, startIndex) != -1){ int index = myRtb.Text.IndexOf(word, startIndex);？我认为你应该在 while 循环中保存找到的索引。
看起来这样就可以了。
http://www.dotnetcurry.com/ShowArticle.aspx?ID=146
int start = 0;
int indexOfSearchText = 0;
private void btnFind_Click(object sender, EventArgs e)
{
int startindex = 0;
if(txtSearch.Text.Length > 0)
startindex = FindMyText(txtSearch.Text.Trim(), start, rtb.Text.Length);
// If string was found in the RichTextBox, highlight it
if (startindex >= 0)
{
// Set the highlight color as red
rtb.SelectionColor = Color.Red;
// Find the end index. End Index = number of characters in textbox
int endindex = txtSearch.Text.Length;
// Highlight the search string
rtb.Select(startindex, endindex);
// mark the start position after the position of
// last search string
start = startindex + endindex;
}
}
public int FindMyText(string txtToSearch, int searchStart, int searchEnd)
{
// Unselect the previously searched string
if (searchStart > 0 && searchEnd > 0 && indexOfSearchText >= 0)
{
rtb.Undo();
}
// Set the return value to -1 by default.
int retVal = -1;
// A valid starting index should be specified.
// if indexOfSearchText = -1, the end of search
if (searchStart >= 0 && indexOfSearchText >=0)
{
// A valid ending index
if (searchEnd > searchStart || searchEnd == -1)
{
// Find the position of search string in RichTextBox
indexOfSearchText = rtb.Find(txtToSearch, searchStart, searchEnd, RichTextBoxFinds.None);
// Determine whether the text was found in richTextBox1.
if (indexOfSearchText != -1)
{
// Return the index to the specified search text.
retVal = indexOfSearchText;
}
}
}
return retVal;
}
// Reset the richtextbox when user changes the search string
private void textBox1_TextChanged(object sender, EventArgs e)
{
start = 0;
indexOfSearchText = 0;
}
【讨论】：
这将同时显示所有搜索条件。
使用：1 个文本框（用于输入要搜索的文本）和 1 个按钮（用于运行搜索）。
在文本框中输入您的搜索条件，然后按搜索按钮。
// On Search Button Click: RichTextBox ("rtb") will display all the words inside the document
private void btn_Search_Click(object sender, EventArgs e)
{
try
{
if (rtb.Text != string.Empty)
{// if the ritchtextbox is not empty; highlight the search criteria
int index = 0;
String temp = rtb.Text;
rtb.Text = "";
rtb.Text = temp;
while (index < rtb.Text.LastIndexOf(txt_Search.Text))
{
rtb.Find(txt_Search.Text, index, rtb.TextLength, RichTextBoxFinds.None);
rtb.SelectionBackColor = Color.Yellow;
index = rtb.Text.IndexOf(txt_Search.Text, index) + 1;
rtb.Select();
}
}
}
catch (Exception ex) { MessageBox.Show(ex.Message, "Error"); }
}
}
}
【讨论】：
如果您只想匹配整个单词，您可以使用它，请注意这会忽略大小写，|s\b 表示复数会突出显示，例如猫匹配猫，但不匹配毛毛虫：
public static void HighlightText(RichTextBox myRtb, string word, Color color)
{
if (word == string.Empty)
return;
var reg = new Regex(@"\b" + word + @"(\b|s\b)",RegexOptions.IgnoreCase);
foreach (Match match in reg.Matches(myRtb.Text))
{
myRtb.Select(match.Index, match.Length);
myRtb.SelectionColor = color;
}
myRtb.SelectionLength = 0;
myRtb.SelectionColor = Color.Black;
}
【讨论】：
private void button3_Click(object sender, EventArgs e)
{
if (textBox1.Text != "")
{
for (int i = 0; i < richTextBox1.TextLength; i++)
{
richTextBox1.Find(textBox1.Text, i, RichTextBoxFinds.None);
richTextBox1.SelectionBackColor = Color.Red;
}
}
else
{
for (int i = 0; i < richTextBox1.TextLength; i++)
{
richTextBox1.SelectAll();
richTextBox1.SelectionBackColor = Color.White;
}
}
}[lets make it!][1]
【讨论】：
我会这样做，因为所有其他答案都会突出显示文本，但在您再次搜索后不会将其更改回来。
使用 RichText 查找方法查找搜索词的起始索引。
public int FindMyText(string searchText, int searchStart, int searchEnd)
{
int returnValue = -1;
if (searchText.Length > 0 && searchStart >= 0)
{
if (searchEnd > searchStart || searchEnd == -1)
{
int indexToText = richTextBox1.Find(searchText, searchStart, searchEnd, RichTextBoxFinds.MatchCase);
if (indexToText >= 0)
{
returnValue = indexToText;
}
}
}
return returnValue;
}
使用 Button 或 TextChangeListener 并搜索您的单词。
private void button1_Click(object sender, EventArgs e)
{
// Select the first char in your Richtextbox
richTextBox1.SelectionStart = 0;
richTextBox1.SelectionLength = richTextBox1.TextLength;
// Select until the end
richTextBox1.SelectionColor = Color.Black;
// Make the Text Color black
//Use an Inputfield to add the searching word
var word = txtSearch.Text;
//verify the minimum length otherwise it may freeze if you dont have text inside
if (word.Length > 3)
{
int s_start = richTextBox1.SelectionStart, startIndex = 0, index;
while ((index = FindMyText(word, startIndex, richTextBox1.TextLength)) != -1)
{
// goes through all possible found words and color them blue (starting index to end)
richTextBox1.Select(index, word.Length);
richTextBox1.SelectionColor = Color.Blue;
startIndex = index + word.Length;
}
// Color everything between in color black to highlight only found words
richTextBox1.SelectionStart = startIndex;
richTextBox1.SelectionLength = 0;
richTextBox1.SelectionColor = Color.Black;
}
}
我强烈建议设置最小字长以避免冻结和高内存分配。
【讨论】：