c#包含部分字符串
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c# contains part of string
提问by raze
So I have a list with Materiel-objects. In Materiel I have 15 get and set methods. I want to construct a search-method that loops all the objects in the list, and all of the variables in each Materiel-object. The looping part is easy enough, but I'm struggling with the string-contains-part. The search term could for instance be "acto", and I should get a hit for "Tractor". I have tried using the string-Contains class, but as far as I can figure out, it only checks the string beginning in position 0. So "Tra" gets a hit, but not "acto".
所以我有一个带有Materiel-objects的列表。在 Materiel 中，我有 15 个 get 和 set 方法。我想构建一个搜索方法，循环列表中的所有对象，以及每个 Materiel 对象中的所有变量。循环部分很容易，但我正在努力处理字符串包含部分。例如，搜索词可能是“acto”，我应该会搜索到“拖拉机”。我曾尝试使用 string-Contains 类，但据我所知，它只检查从位置 0 开始的字符串。所以“Tra”得到了命中，但“acto”没有得到命中。
Is there any build in classes, or should I program one myself?
是否有任何内置课程，还是我应该自己编程？
Sorry for the bad explanation.
对不起，不好的解释。
My code. I see now that I get hits for the substring, but also other results :)
我的代码。我现在看到我得到了子字符串的点击，还有其他结果:)
protected void Button_search_Click(object sender, EventArgs e)
{
string searchTerm = TextBox1.Text.ToString().ToLower();
TableRow row;
TableCell cell;
int rowNumber = 1;
foreach (Materiell mat in allItems)
{
if (searchTerm.Contains(mat.itemID.ToString().ToLower()) ||
searchTerm.Contains(mat.manufacturer.ToLower()) ||
searchTerm.Contains(mat.model.ToLower()) ||
searchTerm.Contains(mat.serialNo.ToLower()) ||
searchTerm.Contains(mat.dateProd.ToString().ToLower()) ||
searchTerm.Contains(mat.location.ToLower()) ||
searchTerm.Contains(mat.mainCategory.ToLower()) ||
searchTerm.Contains(mat.subCategory.ToLower()) ||
searchTerm.Contains(mat.dateAcquired.ToString().ToLower()) ||
searchTerm.Contains(mat.price.ToString().ToLower()) ||
searchTerm.Contains(mat.ownerID.ToString().ToLower()) ||
searchTerm.Contains(mat.extra.ToString().ToLower()) ||
searchTerm.Contains(mat.textComment.ToLower()) ||
searchTerm.Contains(mat.active.ToString().ToLower()))
{
row = new TableRow();
row.ID = "row" + rowNumber.ToString();
rowNumber++;
cell = new TableCell();
cell.Text = "<a href=\"#\" class=\"opendiv\">" + mat.itemID.ToString() + "</a>";
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.manufacturer.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.model.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.serialNo.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.dateProd.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.location.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.mainCategory.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.subCategory.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.dateAcquired.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.price.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.ownerID.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.extra.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.ownDefData.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.textComment.ToString();
row.Cells.Add(cell);
cell = new TableCell();
cell.Text = mat.active.ToString();
row.Cells.Add(cell);
Table1.Rows.Add(row);
}
}
}
采纳答案by ilivewithian
"some string".Contains("str")will return true, are you having problems with case sesitivity?
"some string".Contains("str")将返回 true，您是否有区分大小写的问题？
If so you could use this:
如果是这样，你可以使用这个：
public static bool Contains(this string source, string toCheck, StringComparison comp) {
return source.IndexOf(toCheck, comp) >= 0;
}
string title = "STRING";
bool contains = title.Contains("string", StringComparison.OrdinalIgnoreCase);
(Taken from Case insensitive 'Contains(string)')
回答by SkonJeet
Bool doesContain = "Tractor".Contains("acto");
doesContain will be true.
doContain 将是真的。
Contains works on collections, and in this instance I thinkthe string is treated as a collection of chars.
包含对集合的工作，在这种情况下，我认为字符串被视为字符集合。
回答by Doomsknight
Use IndexOf
用 IndexOf
string searchWithinThis = "ABCDEFGHIJKLMNOP";
string searchForThis = "DEF";
int firstCharacter = searchWithinThis.IndexOf(searchForThis);
Console.WriteLine("First occurrence: {0}", firstCharacter);
if substring is not found, it returns -1. Its very useful for also knowing where abouts the string is found.
如果未找到子字符串，则返回 -1。它对于了解字符串的位置非常有用。
回答by Guffa
The string.Containsmethod does look for the substring anywhere in the string.
该string.Contains方法会在字符串中的任何位置查找子字符串。
"asdf".Contains("as") --> True
"asdf".Contains("sd") --> True
"asdf".Contains("df") --> True
"asdf".Contains("xy") --> False
The comparison is however case sensetive, so you might need to convert case if you want to make an case insesetive search:
然而，比较是区分大小写的，因此如果您想进行不区分大小写的搜索，您可能需要转换大小写：
"Asdf".Contains("as") --> False
"Asdf".Contains("As") --> True
"Asdf".ToUpper().Contains("as".ToUpper()) --> True
回答by Sunil Chavan
class SearchInString
{
static void Main()
{
string strn= "A great things are happen with great humans.";
System.Console.WriteLine("'{0}'",strn);
bool case1= strn.StartsWith("A great");
System.Console.WriteLine("starts with 'A great'? {0}", case1);
bool case2= strn.StartsWith("A great", System.StringComparison.OrdinalIgnoreCase);
System.Console.WriteLine("starts with 'A great'? {0} (ignoring case)", case2);
bool case3= strn.EndsWith(".");
System.Console.WriteLine("ends with '.'? {0}", case3);
int start= strn.IndexOf("great");
int end= strn.LastIndexOf("great");
string strn2 = strn.Substring(start, end- start);
System.Console.WriteLine("between two 'great' words: '{0}'", strn2);
}
}
回答by sehe
For shits and giggles I thought it was a nice lunch-break project to come up with a simple, but 'elegant' solution to the Question (as I understood it :)):
对于狗屎和傻笑，我认为提出一个简单但“优雅”的问题解决方案是一个不错的午休项目（据我了解:)）：
E.g.
例如
// I made up a Material class for testing:
public class Materiel
{
public string A { get; set; }
public int B { get; set; }
public DateTime? C { get; set; }
public string D { get; set; }
public Nested E { get; set; }
}
// [...] usage:
foreach (var pattern in new[]{ "World" , "dick", "Dick", "ick", "2012", "Attach" })
Console.WriteLine("{0} records match '{1}'", Database.Search(pattern).Count(), pattern);
Outputs:
输出：
2 records match 'World'
1 records match 'dick'
1 records match 'Dick'
2 records match 'ick'
1 records match '2012'
2 records match 'Attach'
The code also supports
代码还支持
- regex matches
- any property types (e.g. nullable DateTimes or nested classes)
- showing whichproperty matched the pattern/substring
- 正则匹配
- 任何属性类型（例如可为空的 DateTime 或嵌套类）
- 显示哪个属性与模式/子字符串匹配
Enjoy:
享受：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Text.RegularExpressions;
namespace AClient
{
public class Materiel
{
public string A { get; set; }
public int B { get; set; }
public DateTime? C { get; set; }
public string D { get; set; }
public Nested E { get; set; }
}
public struct Nested
{
public string Data { get; set; }
public override string ToString() { return string.Format("Extra: {0}", Data); }
}
public static class FullText
{
public class PropMatched<T> { public PropertyInfo Property; public T Item; }
public static IEnumerable<PropMatched<T> > ByProperty<T>(this IEnumerable<T> items, string substr)
{
return items.ByProperty(new Regex(Regex.Escape(substr), RegexOptions.IgnoreCase));
}
public static IEnumerable<PropMatched<T> > ByProperty<T>(this IEnumerable<T> items, Regex pattern)
{
return items.Select(i => i.MatchingProperties(pattern)).Where(m => null != m);
}
public static IEnumerable<T> Search<T>(this IEnumerable<T> items, string substr)
{
return items.Search(new Regex(Regex.Escape(substr), RegexOptions.IgnoreCase));
}
public static IEnumerable<T> Search<T>(this IEnumerable<T> items, Regex pattern)
{
return items.Where(i => null != i.MatchingProperties(pattern));
}
public static PropMatched<T> MatchingProperties<T>(this T item, Regex pattern)
{
if (null == pattern || null == item) return null;
var properties = item.GetType().GetProperties(BindingFlags.Public | BindingFlags.FlattenHierarchy | BindingFlags.Instance);
var matches = from prop in properties
let val = prop.GetGetMethod(true).Invoke(item, new object[]{})
where pattern.IsMatch((val??"").ToString())
select prop;
var found = matches.FirstOrDefault();
return found == null ? null : new PropMatched<T> {Item = item, Property = found};
}
}
class Client
{
private static readonly IEnumerable<Materiel> Database = new List<Materiel>
{
new Materiel {
A = "Hello", B = 1, C = null, D = "World",
E = new Nested {Data = "Attachment"}
},
new Materiel {
A = "Transfigured", B = 2, C = null, D = "Nights",
E = new Nested {Data = "Schoenberg"}
},
new Materiel {
A = "Moby", B = 3, C = null, D = "Dick",
E = new Nested {Data = "Biographic"}
},
new Materiel {
A = "Prick", B = 4, C = DateTime.Today, D = "World",
E = new Nested {Data = "Attachment"}
},
new Materiel {
A = "Oh Noes", B = 2, C = null, D = "Nights",
E = new Nested {Data = "Schoenberg"}
},
};
static void Main()
{
foreach (var pattern in new[]{ "World" , "dick", "Dick", "ick", "2012", "Attach" })
Console.WriteLine("{0} records match '{1}'", Database.Search(pattern).Count(), pattern);
// regex sample:
var regex = new Regex(@"N\w+s", RegexOptions.IgnoreCase);
Console.WriteLine(@"{0} records match regular expression 'N\w+s'", Database.Search(regex).Count());
// with context info:
foreach (var contextMatch in Database.ByProperty(regex))
{
Console.WriteLine("1 match of regex in propery {0} with value '{1}'",
contextMatch.Property.Name, contextMatch.Property.GetGetMethod().Invoke(contextMatch.Item, new object[0]));
}
}
}
}
