已解决。这段代码在iOS端执行的时候，有些字符可能无法识别导致的问题。

decodeHtml(str) {

if (typeof str != "string") {

return str;

}

if (str == null || str.length == 0) return "";

str = str.replace(/ /g, ' ');

str = str.replace(/¡/g, '¡');

str = str.replace(/¢/g, '¢');

str = str.replace(/£/g, '£');

str = str.replace(/¤/g, '¤');

str = str.replace(/¥/g, '¥');

str = str.replace(/¦/g, '¦');

str = str.replace(/§/g, '§');

str = str.replace(/¨/g, '¨');

str = str.replace(/©/g, '©');

str = str.replace(/ª/g, 'ª');

str = str.replace(/«/g, '«');

str = str.replace(/¬/g, '¬');

str = str.replace(/­/g, '­');

str = str.replace(/®/g, '®');

str = str.replace(/¯/g, '¯');

str = str.replace(/°/g, '°');

str = str.replace(/±/g, '±');

str = str.replace(/²/g, '²');

str = str.replace(/³/g, '³');

str = str.replace(/´/g, '´');

str = str.replace(/µ/g, 'µ');

str = str.replace(/¶/g, '¶');

str = str.replace(/·/g, '·');

str = str.replace(/¸/g, '¸');

str = str.replace(/¹/g, '¹');

str = str.replace(/º/g, 'º');

str = str.replace(/»/g, '»');

str = str.replace(/¼/g, '¼');

str = str.replace(/½/g, '½');

str = str.replace(/¾/g, '¾');

str = str.replace(/¿/g, '¿');

str = str.replace(/À/g, 'À');

str = str.replace(/Á/g, 'Á');

str = str.replace(/Â/g, 'Â');

str = str.replace(/Ã/g, 'Ã');

str = str.replace(/Ä/g, 'Ä');

str = str.replace(/Å/g, 'Å');

str = str.replace(/Æ/g, 'Æ');

str = str.replace(/Ç/g, 'Ç');

str = str.replace(/È/g, 'È');

str = str.replace(/É/g, 'É');

str = str.replace(/Ê/g, 'Ê');

str = str.replace(/Ë/g, 'Ë');

str = str.replace(/Ì/g, 'Ì');

str = str.replace(/Í/g, 'Í');

str = str.replace(/Î/g, 'Î');

str = str.replace(/Ï/g, 'Ï');

str = str.replace(/Ð/g, 'Ð');

str = str.replace(/Ñ/g, 'Ñ');

str = str.replace(/Ò/g, 'Ò');

str = str.replace(/Ó/g, 'Ó');

str = str.replace(/Ô/g, 'Ô');

str = str.replace(/Õ/g, 'Õ');

str = str.replace(/Ö/g, 'Ö');

str = str.replace(/×/g, '×');

str = str.replace(/Ø/g, 'Ø');

str = str.replace(/Ù/g, 'Ù');

str = str.replace(/Ú/g, 'Ú');

str = str.replace(/Û/g, 'Û');

str = str.replace(/Ü/g, 'Ü');

str = str.replace(/Ý/g, 'Ý');

str = str.replace(/Þ/g, 'Þ');

str = str.replace(/ß/g, 'ß');

str = str.replace(/à/g, 'à');

str = str.replace(/á/g, 'á');

str = str.replace(/â/g, 'â');

str = str.replace(/ã/g, 'ã');

str = str.replace(/ä/g, 'ä');

str = str.replace(/å/g, 'å');

str = str.replace(/æ/g, 'æ');

str = str.replace(/ç/g, 'ç');

str = str.replace(/è/g, 'è');

str = str.replace(/é/g, 'é');

str = str.replace(/ê/g, 'ê');

str = str.replace(/ë/g, 'ë');

str = str.replace(/ì/g, 'ì');

str = str.replace(/í/g, 'í');

str = str.replace(/î/g, 'î');

str = str.replace(/ï/g, 'ï');

str = str.replace(/ð/g, 'ð');

str = str.replace(/ñ/g, 'ñ');

str = str.replace(/ò/g, 'ò');

str = str.replace(/ó/g, 'ó');

str = str.replace(/ô/g, 'ô');

str = str.replace(/õ/g, 'õ');

str = str.replace(/ö/g, 'ö');

str = str.replace(/÷/g, '÷');

str = str.replace(/ø/g, 'ø');

str = str.replace(/ù/g, 'ù');

str = str.replace(/ú/g, 'ú');

str = str.replace(/û/g, 'û');

str = str.replace(/ü/g, 'ü');

str = str.replace(/ý/g, 'ý');

str = str.replace(/þ/g, 'þ');

str = str.replace(/ÿ/g, 'ÿ');

str = str.replace(/ƒ/g, 'ƒ');

str = str.replace(/Α/g, 'Α');

str = str.replace(/Β/g, 'Β');

str = str.replace(/Γ/g, 'Γ');

str = str.replace(/Δ/g, 'Δ');

str = str.replace(/Ε/g, 'Ε');

str = str.replace(/Ζ/g, 'Ζ');

str = str.replace(/Η/g, 'Η');

str = str.replace(/Θ/g, 'Θ');

str = str.replace(/Ι/g, 'Ι');

str = str.replace(/Κ/g, 'Κ');

str = str.replace(/Λ/g, 'Λ');

str = str.replace(/Μ/g, 'Μ');

str = str.replace(/Ν/g, 'Ν');

str = str.replace(/Ξ/g, 'Ξ');

str = str.replace(/Ο/g, 'Ο');

str = str.replace(/Π/g, 'Π');

str = str.replace(/Ρ/g, 'Ρ');

str = str.replace(/Σ/g, 'Σ');

str = str.replace(/Τ/g, 'Τ');

str = str.replace(/Υ/g, 'Υ');

str = str.replace(/Φ/g, 'Φ');

str = str.replace(/Χ/g, 'Χ');

str = str.replace(/Ψ/g, 'Ψ');

str = str.replace(/Ω/g, 'Ω');

str = str.replace(/α/g, 'α');

str = str.replace(/β/g, 'β');

str = str.replace(/γ/g, 'γ');

str = str.replace(/δ/g, 'δ');

str = str.replace(/ε/g, 'ε');

str = str.replace(/ζ/g, 'ζ');

str = str.replace(/η/g, 'η');

str = str.replace(/θ/g, 'θ');

str = str.replace(/ι/g, 'ι');

str = str.replace(/κ/g, 'κ');

str = str.replace(/λ/g, 'λ');

str = str.replace(/μ/g, 'μ');

str = str.replace(/ν/g, 'ν');

str = str.replace(/ξ/g, 'ξ');

str = str.replace(/ο/g, 'ο');

str = str.replace(/π/g, 'π');

str = str.replace(/ρ/g, 'ρ');

str = str.replace(/ς/g, 'ς');

str = str.replace(/σ/g, 'σ');

str = str.replace(/τ/g, 'τ');

str = str.replace(/υ/g, 'υ');

str = str.replace(/φ/g, 'φ');

str = str.replace(/χ/g, 'χ');

str = str.replace(/ψ/g, 'ψ');

str = str.replace(/ω/g, 'ω');

str = str.replace(/ϑ/g, 'ϑ');

str = str.replace(/ϒ/g, 'ϒ');

str = str.replace(/ϖ/g, 'ϖ');

str = str.replace(/•/g, '•');

str = str.replace(/…/g, '…');

str = str.replace(/′/g, '′');

str = str.replace(/″/g, '″');

str = str.replace(/‾/g, '‾');

str = str.replace(/⁄/g, '⁄');

str = str.replace(/℘/g, '℘');

str = str.replace(/ℑ/g, 'ℑ');

str = str.replace(/ℜ/g, 'ℜ');

str = str.replace(/™/g, '™');

str = str.replace(/ℵ/g, 'ℵ');

str = str.replace(/←/g, '←');

str = str.replace(/↑/g, '↑');

str = str.replace(/→/g, '→');

str = str.replace(/↓/g, '↓');

str = str.replace(/↔/g, '↔');

str = str.replace(/↵/g, '↵');

str = str.replace(/⇐/g, '⇐');

str = str.replace(/⇑/g, '⇑');

str = str.replace(/⇒/g, '⇒');

str = str.replace(/⇓/g, '⇓');

str = str.replace(/⇔/g, '⇔');

str = str.replace(/∀/g, '∀');

str = str.replace(/∂/g, '∂');

str = str.replace(/∃/g, '∃');

str = str.replace(/∅/g, '∅');

str = str.replace(/∇/g, '∇');

str = str.replace(/∈/g, '∈');

str = str.replace(/∉/g, '∉');

str = str.replace(/∋/g, '∋');

str = str.replace(/∏/g, '∏');

str = str.replace(/∑/g, '∑');

str = str.replace(/−/g, '−');

str = str.replace(/∗/g, '∗');

str = str.replace(/√/g, '√');

str = str.replace(/∝/g, '∝');

str = str.replace(/∞/g, '∞');

str = str.replace(/∠/g, '∠');

str = str.replace(/∧/g, '∧');

str = str.replace(/∨/g, '∨');

str = str.replace(/∩/g, '∩');

str = str.replace(/∪/g, '∪');

str = str.replace(/∫/g, '∫');

str = str.replace(/∴/g, '∴');

str = str.replace(/∼/g, '∼');

str = str.replace(/≅/g, '≅');

str = str.replace(/≈/g, '≈');

str = str.replace(/≠/g, '≠');

str = str.replace(/≡/g, '≡');

str = str.replace(/≤/g, '≤');

str = str.replace(/≥/g, '≥');

str = str.replace(/⊂/g, '⊂');

str = str.replace(/⊃/g, '⊃');

str = str.replace(/⊄/g, '⊄');

str = str.replace(/⊆/g, '⊆');

str = str.replace(/⊇/g, '⊇');

str = str.replace(/⊕/g, '⊕');

str = str.replace(/⊗/g, '⊗');

str = str.replace(/⊥/g, '⊥');

str = str.replace(/⋅/g, '⋅');

str = str.replace(/⌈/g, '⌈');

str = str.replace(/⌉/g, '⌉');

str = str.replace(/⌊/g, '⌊');

str = str.replace(/⌋/g, '⌋');

str = str.replace(/⟨/g, '〈');

str = str.replace(/⟩/g, '〉');

str = str.replace(/◊/g, '◊');

str = str.replace(/♠/g, '♠');

str = str.replace(/♣/g, '♣');

str = str.replace(/♥/g, '♥');

str = str.replace(/♦/g, '♦');

str = str.replace(/Œ/g, 'Œ');

str = str.replace(/œ/g, 'œ');

str = str.replace(/Š/g, 'Š');

str = str.replace(/š/g, 'š');

str = str.replace(/Ÿ/g, 'Ÿ');

str = str.replace(/ˆ/g, 'ˆ');

str = str.replace(/˜/g, '˜');

str = str.replace(/ /g, ' ');

str = str.replace(/ /g, ' ');

str = str.replace(/ /g, ' ');

str = str.replace(/‌/g, '‌');

str = str.replace(/‍/g, '‍');

str = str.replace(/‎/g, '‎');

str = str.replace(/‏/g, '‏');

str = str.replace(/–/g, '–');

str = str.replace(/—/g, '—');

str = str.replace(/‘/g, '‘');

str = str.replace(/’/g, '’');

str = str.replace(/‚/g, '‚');

str = str.replace(/“/g, '“');

str = str.replace(/”/g, '”');

str = str.replace(/„/g, '„');

str = str.replace(/†/g, '†');

str = str.replace(/‡/g, '‡');

str = str.replace(/‰/g, '‰');

str = str.replace(/‹/g, '‹');

str = str.replace(/›/g, '›');

str = str.replace(/€/g, '€');

str = str.replace(/"/g, '"');

str = str.replace(/&lt;/g, '<');

str = str.replace(/&gt;/g, '>');

str = str.replace(/&apos;/g, '\'');

str = str.replace(/&#39;/g, '\'');

str = str.replace(/&amp;/g, '&');

return str;

}