Use Array.Copy in Match.AddMatch (#122894)

stephentoub · web-flow · commit ee72dc8409a2 · 2026-01-05T21:30:55.000Z
diff --git a/src/libraries/System.Text.RegularExpressions/src/System/Text/RegularExpressions/Match.cs b/src/libraries/System.Text.RegularExpressions/src/System/Text/RegularExpressions/Match.cs
@@ -177,10 +177,7 @@ internal void AddMatch(int cap, int start, int len)
             {
                 int[] oldmatches = matches[cap];
                 int[] newmatches = new int[capcount * 8];
-                for (int j = 0; j < capcount * 2; j++)
-                {
-                    newmatches[j] = oldmatches[j];
-                }
+                Array.Copy(oldmatches, newmatches, capcount * 2);
 
                 matches[cap] = newmatches;
             }

Original file line number	Diff line number	Diff line change
`@@ -177,10 +177,7 @@ internal void AddMatch(int cap, int start, int len)`
`177`	`177`	`{`
`178`	`178`	`int[] oldmatches = matches[cap];`
`179`	`179`	`int[] newmatches = new int[capcount * 8];`
`180`		`- for (int j = 0; j < capcount * 2; j++)`
`181`		`- {`
`182`		`- newmatches[j] = oldmatches[j];`
`183`		`- }`
	`180`	`+ Array.Copy(oldmatches, newmatches, capcount * 2);`
`184`	`181`
`185`	`182`	`matches[cap] = newmatches;`
`186`	`183`	`}`